Fumarate analogs and uses thereof

ABSTRACT

Aspects of the present disclosure include compounds that find use for the treatment of a variety of autoimmune and inflammatory diseases and disorders. Embodiments of the present disclosure also relate to pharmaceutical compositions that include these compounds, methods of using these compounds in the treatment of various diseases and disorders, processes for preparing these compounds and intermediates useful in these processes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/815,589, filed Jul. 31, 2015, which claims benefit under 35 U.S.C.§119(e) of U.S. Provisional Application No. 62/033,023, filed Aug. 4,2014, the disclosures of each of which are incorporated herein byreference in their entirety.

INTRODUCTION

Fumaric acid is an intermediate product of the citric acid cycle.Fumaric acid is a source of intracellular energy in the form ofadenosine triphosphate (ATP), and is generated by oxidation ofadenylsuccinate by the enzyme succinate dehydrogenase which is thenconverted to maleate by the enzyme fumarase. Fumaric acid esters (FAE),such as dimethylfumarate (DMF) have been used in the treatment ofpsoriasis and multiple sclerosis. After oral intake, DMF is rapidlyhydrolyzed by esterases to its metabolite monomethyl fumarate (MMF).

Multiple sclerosis (MS), also known as disseminated sclerosis orencephalomyelitis disseminata, is an inflammatory disease in which theinsulating covers of nerve cells in the brain and spinal cord aredamaged. This damage disrupts the ability of parts of the nervous systemto communicate. The three main characteristics of MS are the formationof lesions in the central nervous system (also called plaques),inflammation, and the destruction of myelin sheaths of neurons. MS maybe caused by either destruction of the myelin sheaths of neurons by theimmune system or failure of the myelin-producing cells.

Psoriasis is a chronic relapsing/remitting immune-mediated skin diseasecharacterized by red, scaly patches, papules, and plaques. There arefive main types of psoriasis: plaque, guttate, inverse, pustular, anderythrodermic. Plaque psoriasis is the most common form and typicalsymptoms are red and white scaly patches on the top layer of the skin.Psoriasis is thought to be caused when the immune system mistakes normalskin cells for a pathogen, and secretes inflammatory chemical signals(cytokines) that cause overproduction of new skin cells.

SUMMARY

Aspects of the present disclosure include compounds that find use forthe treatment of a variety of autoimmune and inflammatory diseases anddisorders. Embodiments of the present disclosure also relate topharmaceutical compositions that include these compounds, methods ofusing these compounds in the treatment of various diseases anddisorders, processes for preparing these compounds and intermediatesuseful in these processes.

Embodiments of the compounds are provided throughout the disclosure. Forexample, such compounds are represented by the following formula (A):

wherein either:

Y¹ is X^(a) and Y² is hydrogen, or Y² is X^(a) and Y¹ is hydrogen;

wherein X^(a) is selected from carboxylic acid, carboxyl ester,heterocyclyl, substituted heterocyclyl, heteroaryl and substitutedheteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (A);

or a salt or stereoisomer thereof.

In some embodiments of formula (A), the compounds are represented byformula (Ia) or (Ib):

wherein

X^(a) is selected from carboxylic acid, carboxyl ester, heterocyclyl,substituted heterocyclyl, heteroaryl and substituted heteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (Ia) or (Ib);

or a salt or stereoisomer thereof.

In some embodiments, such compounds are represented by the followingformula (Ia):

wherein

X^(a) is selected from carboxylic acid, carboxyl ester, heterocyclyl,substituted heterocyclyl, heteroaryl and substituted heteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (Ia);

or a salt or stereoisomer thereof.

In some embodiments, such compounds are represented by formula (Ib):

wherein

X^(a) is selected from carboxylic acid, carboxyl ester, heterocyclyl,substituted heterocyclyl, heteroaryl and substituted heteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (Ib);

or a salt or stereoisomer thereof.

In some embodiments, the compound is a compound of formula (IIa) or(IIb):

wherein

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (IIa) or (IIb);and

X¹ is hydrogen, C₁₋₆ alkyl or a progroup;

or a salt or stereoisomer thereof.

In some embodiments, the compound is a compound of formula (IIa):

wherein

R¹ is hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl,alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, and —R¹⁵ where R¹⁵ includes alinking group and a compound of formula (IIa); and

X is C₁₋₆ alkyl or a progroup;

or a salt or stereoisomer thereof.

In some embodiments, the compound is a dimer, where R¹⁵ includes alinking group and a compound of formula (Ia) or (Ib). In someembodiments, the compound is a dimer, where R¹⁵ includes a linking groupand a compound of formula (IIa) or (IIb).

In some embodiments, the compound is a compound of formula (IIb):

wherein

R¹ is hydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl,alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, and —R¹⁵ where R¹⁵ includes alinking group and a compound of formula (IIb); and

X¹ is C₁₋₆ alkyl or a progroup;

or a salt or stereoisomer thereof.

Embodiments of the present disclosure also include a pharmaceuticalcomposition that includes a compound as described herein. In someembodiments, the pharmaceutical composition includes a pharmaceuticallyacceptable carrier.

Embodiments of the present disclosure also include a method of treatinga disease or disorder in a subject by administering a pharmaceuticallyacceptable amount of a compound as described herein sufficient to treatthe disease or disorder. In some embodiments, the disease or disorder isan autoimmune disease or an inflammatory disease. In some embodiments,the disease or disorder is psoriasis or multiple sclerosis.

DETAILED DESCRIPTION

Aspects of the present disclosure include compounds that find use forthe treatment of a variety of autoimmune and inflammatory diseases anddisorders. Embodiments of the present disclosure also relate topharmaceutical compositions that include these compounds, methods ofusing these compounds in the treatment of various diseases anddisorders, processes for preparing these compounds and intermediatesuseful in these processes.

Before the present invention is further described, it is to beunderstood that this invention is not limited to particular embodimentsdescribed, as such may, of course, vary. It is also to be understoodthat the terminology used herein is for the purpose of describingparticular embodiments only, and is not intended to be limiting, sincethe scope of the present invention will be limited only by the appendedclaims.

It must be noted that as used herein and in the appended claims, thesingular forms “a,” “an,” and “the” include plural referents unless thecontext clearly dictates otherwise. It is further noted that the claimsmay be drafted to exclude any optional element. As such, this statementis intended to serve as antecedent basis for use of such exclusiveterminology as “solely,” “only” and the like in connection with therecitation of claim elements, or use of a “negative” limitation.

Where a range of values is provided, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimit of that range and any other stated or intervening value in thatstated range, is specifically contemplated. The upper and lower limitsof these smaller ranges may independently be included in the smallerranges, and are also encompassed within the invention, subject to anyspecifically excluded limit in the stated range. Where the stated rangeincludes one or both of the limits, ranges excluding either or both ofthose included limits are also included in the invention.

The publications discussed herein are provided solely for theirdisclosure prior to the filing date of the present application. Nothingherein is to be construed as an admission that the present invention isnot entitled to antedate such publication by virtue of prior invention.Further, the dates of publication provided may be different from theactual publication dates which may need to be independently confirmed.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although any methods andmaterials similar or equivalent to those described herein can also beused in the practice or testing of the present invention, the preferredmethods and materials are now described. All publications mentionedherein are incorporated herein by reference to disclose and describe themethods and/or materials in connection with which the publications arecited.

Except as otherwise noted, the methods and techniques of the presentembodiments are generally performed according to conventional methodswell known in the art and as described in various general and morespecific references that are cited and discussed throughout the presentspecification. See, e.g., Loudon, Organic Chemistry, Fourth Edition, NewYork: Oxford University Press, 2002, pp. 360-361, 1084-1085; Smith andMarch, March's Advanced Organic Chemistry: Reactions, Mechanisms, andStructure, Fifth Edition, Wiley-Interscience, 2001; or Vogel, A Textbookof Practical Organic Chemistry, Including Qualitative Organic Analysis,Fourth Edition, New York: Longman, 1978.

The nomenclature used herein to name the subject compounds isillustrated in the Examples herein. This nomenclature has generally beenderived using the commercially-available AutoNom software (MDL, SanLeandro, Calif.).

Terms

The following terms have the following meanings unless otherwiseindicated. Any undefined terms have their art recognized meanings.

“Alkyl” refers to monovalent saturated aliphatic hydrocarbyl groupshaving from 1 to 10 carbon atoms and preferably 1 to 6 carbon atoms.This term includes, by way of example, linear and branched hydrocarbylgroups such as methyl (CH₃—), ethyl (CH₃CH₂—), n-propyl (CH₃CH₂CH₂—),isopropyl ((CH₃)₂CH—), n-butyl (CH₃CH₂CH₂CH₂—), isobutyl ((CH₃)₂CHCH₂—),sec-butyl ((CH₃)(CH₃CH₂)CH—), t-butyl ((CH₃)₃C—), n-pentyl(CH₃CH₂CH₂CH₂CH₂—), and neopentyl ((CH₃)₃CCH₂—).

The term “substituted alkyl” refers to an alkyl group as defined hereinwherein one or more carbon atoms in the alkyl chain (except the C₁carbon atom) have been optionally replaced with a heteroatom such as—O—, —N—, —S—, —S(O)_(n)— (where n is 0 to 2), —NR— (where R is hydrogenor alkyl) and having from 1 to 5 substituents selected from the groupconsisting of alkoxy, substituted alkoxy, cycloalkyl, substitutedcycloalkyl, cycloalkenyl, substituted cycloalkenyl, acyl, acylamino,acyloxy, amino, aminoacyl, aminoacyloxy, oxyaminoacyl, azido, cyano,halogen, hydroxyl, oxo, thioketo, carboxyl, carboxylalkyl, thioaryloxy,thioheteroaryloxy, thioheterocyclooxy, thiol, thioalkoxy, substitutedthioalkoxy, aryl, aryloxy, heteroaryl, heteroaryloxy, heterocyclyl,heterocyclooxy, hydroxyamino, alkoxyamino, nitro, —SO-alkyl, —SO-aryl,—SO-heteroaryl, —SO₂-alkyl, —SO₂-aryl, —SO₂-heteroaryl, and—NR^(a)R^(b), wherein R′ and R″ may be the same or different and arechosen from hydrogen, optionally substituted alkyl, cycloalkyl, alkenyl,cycloalkenyl, alkynyl, aryl, heteroaryl and heterocyclic.

“Alkylene” refers to divalent aliphatic hydrocarbyl groups preferablyhaving from 1 to 6 and more preferably 1 to 3 carbon atoms that areeither straight-chained or branched, and which are optionallyinterrupted with one or more groups selected from —O—, —NR¹⁰—,—NR¹⁰C(O)—, —C(O)NR¹⁰— and the like. This term includes, by way ofexample, methylene (—CH₂—), ethylene (—CH₂CH₂—), n-propylene(—CH₂CH₂CH₂—), iso-propylene (—CH₂CH(CH₃)—), (—C(CH₃)₂CH₂CH₂—),(—C(CH₃)₂CH₂C(O)—), (—C(CH₃)₂CH₂C(O)NH—), (—CH(CH₃)CH₂—), and the like.

“Substituted alkylene” refers to an alkylene group having from 1 to 3hydrogens replaced with substituents as described for carbons in thedefinition of “substituted” below.

The term “alkane” refers to alkyl group and alkylene group, as definedherein.

The term “alkylaminoalkyl”, “alkylaminoalkenyl” and “alkylaminoalkynyl”refers to the groups R′NHR″— where R′ is alkyl group as defined hereinand R″ is alkylene, alkenylene or alkynylene group as defined herein.

The term “alkaryl” or “aralkyl” refers to the groups -alkylene-aryl and-substituted alkylene-aryl where alkylene, substituted alkylene and arylare defined herein.

“Alkoxy” refers to the group —O-alkyl, wherein alkyl is as definedherein. Alkoxy includes, by way of example, methoxy, ethoxy, n-propoxy,isopropoxy, n-butoxy, t-butoxy, sec-butoxy, n-pentoxy, and the like. Theterm “alkoxy” also refers to the groups alkenyl-O—, cycloalkyl-O—,cycloalkenyl-O—, and alkynyl-O—, where alkenyl, cycloalkyl,cycloalkenyl, and alkynyl are as defined herein.

The term “substituted alkoxy” refers to the groups substituted alkyl-O—,substituted alkenyl-O—, substituted cycloalkyl-O—, substitutedcycloalkenyl-O—, and substituted alkynyl-O— where substituted alkyl,substituted alkenyl, substituted cycloalkyl, substituted cycloalkenyland substituted alkynyl are as defined herein.

The term “alkoxyamino” refers to the group —NH-alkoxy, wherein alkoxy isdefined herein.

The term “haloalkoxy” refers to the groups alkyl-O— wherein one or morehydrogen atoms on the alkyl group have been substituted with a halogroup and include, by way of examples, groups such as trifluoromethoxy,and the like.

The term “haloalkyl” refers to a substituted alkyl group as describedabove, wherein one or more hydrogen atoms on the alkyl group have beensubstituted with a halo group. Examples of such groups include, withoutlimitation, fluoroalkyl groups, such as trifluoromethyl, difluoromethyl,trifluoroethyl and the like.

The term “alkylalkoxy” refers to the groups -alkylene-O-alkyl,alkylene-O-substituted alkyl, substituted alkylene-O-alkyl, andsubstituted alkylene-O-substituted alkyl wherein alkyl, substitutedalkyl, alkylene and substituted alkylene are as defined herein.

The term “alkylthioalkoxy” refers to the group -alkylene-S-alkyl,alkylene-S-substituted alkyl, substituted alkylene-S-alkyl andsubstituted alkylene-S-substituted alkyl wherein alkyl, substitutedalkyl, alkylene and substituted alkylene are as defined herein.

“Alkenyl” refers to straight chain or branched hydrocarbyl groups havingfrom 2 to 6 carbon atoms and preferably 2 to 4 carbon atoms and havingat least 1 and preferably from 1 to 2 sites of double bond unsaturation.This term includes, by way of example, bi-vinyl, allyl, andbut-3-en-1-yl. Included within this term are the cis and trans isomersor mixtures of these isomers.

The term “substituted alkenyl” refers to an alkenyl group as definedherein having from 1 to 5 substituents, or from 1 to 3 substituents,selected from alkoxy, substituted alkoxy, cycloalkyl, substitutedcycloalkyl, cycloalkenyl, substituted cycloalkenyl, acyl, acylamino,acyloxy, amino, substituted amino, aminoacyl, aminoacyloxy,oxyaminoacyl, azido, cyano, halogen, hydroxyl, oxo, thioketo, carboxyl,carboxylalkyl, thioaryloxy, thioheteroaryloxy, thioheterocyclooxy,thiol, thioalkoxy, substituted thioalkoxy, aryl, aryloxy, heteroaryl,heteroaryloxy, heterocyclyl, heterocyclooxy, hydroxyamino, alkoxyamino,nitro, —SO-alkyl, —SO— substituted alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryl and —SO₂-heteroaryl.

“Alkynyl” refers to straight or branched monovalent hydrocarbyl groupshaving from 2 to 6 carbon atoms and preferably 2 to 3 carbon atoms andhaving at least 1 and preferably from 1 to 2 sites of triple bondunsaturation. Examples of such alkynyl groups include acetylenyl(—C≡CH), and propargyl (—CH₂C≡CH).

The term “substituted alkynyl” refers to an alkynyl group as definedherein having from 1 to 5 substituents, or from 1 to 3 substituents,selected from alkoxy, substituted alkoxy, cycloalkyl, substitutedcycloalkyl, cycloalkenyl, substituted cycloalkenyl, acyl, acylamino,acyloxy, amino, substituted amino, aminoacyl, aminoacyloxy,oxyaminoacyl, azido, cyano, halogen, hydroxyl, oxo, thioketo, carboxyl,carboxylalkyl, thioaryloxy, thioheteroaryloxy, thioheterocyclooxy,thiol, thioalkoxy, substituted thioalkoxy, aryl, aryloxy, heteroaryl,heteroaryloxy, heterocyclyl, heterocyclooxy, hydroxyamino, alkoxyamino,nitro, —SO-alkyl, —SO— substituted alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryl, and —SO₂-heteroaryl.

“Alkynyloxy” refers to the group —O-alkynyl, wherein alkynyl is asdefined herein. Alkynyloxy includes, by way of example, ethynyloxy,propynyloxy, and the like.

“Acyl” refers to the groups H—C(O)—, alkyl-C(O)—, substitutedalkyl-C(O)—, alkenyl-C(O)—, substituted alkenyl-C(O)—, alkynyl-C(O)—,substituted alkynyl-C(O)—, cycloalkyl-C(O)—, substitutedcycloalkyl-C(O)—, cycloalkenyl-C(O)—, substituted cycloalkenyl-C(O)—,aryl-C(O)—, substituted aryl-C(O)—, heteroaryl-C(O)—, substitutedheteroaryl-C(O)—, heterocyclyl-C(O)—, and substitutedheterocyclyl-C(O)—, wherein alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, andsubstituted heterocyclic are as defined herein. For example, acylincludes the “acetyl” group CH₃C(O)—

“Acylamino” refers to the groups —NR²⁰C(O)alkyl, —NR²⁰C(O) substitutedalkyl, NR²⁰C(O)cycloalkyl, —NR²⁰C(O) substituted cycloalkyl,—NR²⁰C(O)cycloalkenyl, —NR²⁰C(O) substituted cycloalkenyl,—NR²⁰C(O)alkenyl, —NR²⁰C(O) substituted alkenyl, —NR²⁰C(O)alkynyl,—NR²⁰C(O) substituted alkynyl, —NR²⁰C(O)aryl, —NR²⁰C(O) substitutedaryl, —NR²⁰C(O)heteroaryl, —NR²⁰C(O) substituted heteroaryl,—NR²⁰C(O)heterocyclic, and —NR²⁰C(O) substituted heterocyclic, whereinR²⁰ is hydrogen or alkyl and wherein alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, andsubstituted heterocyclic are as defined herein.

“Aminocarbonyl” or the term “aminoacyl” refers to the group—C(O)NR²¹R²², wherein R²¹ and R²² independently are selected from thegroup consisting of hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, aryl, substitutedaryl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, heteroaryl, substituted heteroaryl, heterocyclic, andsubstituted heterocyclic and where R²¹ and R²² are optionally joinedtogether with the nitrogen bound thereto to form a heterocyclic orsubstituted heterocyclic group, and wherein alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, andsubstituted heterocyclic are as defined herein.

“Aminocarbonylamino” refers to the group —NR²¹C(O)NR²²R²³ where R²¹,R²², and R²³ are independently selected from hydrogen, alkyl, aryl orcycloalkyl, or where two R groups are joined to form a heterocyclylgroup.

The term “alkoxycarbonylamino” refers to the group —NRC(O)OR where eachR is independently hydrogen, alkyl, substituted alkyl, aryl, heteroaryl,or heterocyclyl wherein alkyl, substituted alkyl, aryl, heteroaryl, andheterocyclyl are as defined herein.

The term “acyloxy” refers to the groups alkyl-C(O)O—, substitutedalkyl-C(O)O—, cycloalkyl-C(O)O—, substituted cycloalkyl-C(O)O—,aryl-C(O)O—, heteroaryl-C(O)O—, and heterocyclyl-C(O)O— wherein alkyl,substituted alkyl, cycloalkyl, substituted cycloalkyl, aryl, heteroaryl,and heterocyclyl are as defined herein.

“Aminosulfonyl” refers to the group —SO₂NR²¹R²², wherein R²¹ and R²²independently are selected from the group consisting of hydrogen, alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl,cycloalkenyl, substituted cycloalkenyl, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic and where R²¹ and R²²are optionally joined together with the nitrogen bound thereto to form aheterocyclic or substituted heterocyclic group and alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Sulfonylamino” refers to the group —NR²¹SO₂R²², wherein R²¹ and R²²independently are selected from the group consisting of hydrogen, alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl,cycloalkenyl, substituted cycloalkenyl, heteroaryl, substitutedheteroaryl, heterocyclic, and substituted heterocyclic and where R²¹ andR²² are optionally joined together with the atoms bound thereto to forma heterocyclic or substituted heterocyclic group, and wherein alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic, and substituted heterocyclic are as definedherein.

“Aryl” or “Ar” refers to a monovalent aromatic carbocyclic group of from6 to 18 carbon atoms having a single ring (such as is present in aphenyl group) or a ring system having multiple condensed rings (examplesof such aromatic ring systems include naphthyl, anthryl and indanyl)which condensed rings may or may not be aromatic, provided that thepoint of attachment is through an atom of an aromatic ring. This termincludes, by way of example, phenyl and naphthyl. Unless otherwiseconstrained by the definition for the aryl substituent, such aryl groupscan optionally be substituted with from 1 to 5 substituents, or from 1to 3 substituents, selected from acyloxy, hydroxy, thiol, acyl, alkyl,alkoxy, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, substituted alkyl,substituted alkoxy, substituted alkenyl, substituted alkynyl,substituted cycloalkyl, substituted cycloalkenyl, amino, substitutedamino, aminoacyl, acylamino, alkaryl, aryl, aryloxy, azido, carboxyl,carboxylalkyl, cyano, halogen, nitro, heteroaryl, heteroaryloxy,heterocyclyl, heterocyclooxy, aminoacyloxy, oxyacylamino, thioalkoxy,substituted thioalkoxy, thioaryloxy, thioheteroaryloxy, —SO-alkyl,—SO-substituted alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-aryl, —SO₂-heteroaryl and trihalomethyl.

“Aryloxy” refers to the group —O-aryl, wherein aryl is as definedherein, including, by way of example, phenoxy, naphthoxy, and the like,including optionally substituted aryl groups as also defined herein.

“Amino” refers to the group —NH₂.

The term “substituted amino” refers to the group —NRR where each R isindependently selected from the group consisting of hydrogen, alkyl,substituted alkyl, cycloalkyl, substituted cycloalkyl, alkenyl,substituted alkenyl, cycloalkenyl, substituted cycloalkenyl, alkynyl,substituted alkynyl, aryl, heteroaryl, and heterocyclyl provided that atleast one R is not hydrogen.

The term “azido” refers to the group —N₃.

“Carboxyl,” “carboxy” or “carboxylate” refers to —CO₂H or salts thereof.

“Carboxyl ester” or “carboxy ester” or the terms “carboxyalkyl” or“carboxylalkyl” refers to the groups —C(O)O-alkyl, —C(O)O-substitutedalkyl, —C(O)O-alkenyl, —C(O)O-substituted alkenyl, —C(O)O-alkynyl,—C(O)O-substituted alkynyl, —C(O)O-aryl, —C(O)O-substituted aryl,—C(O)O-cycloalkyl, —C(O)O-substituted cycloalkyl, —C(O)O-cycloalkenyl,—C(O)O-substituted cycloalkenyl, —C(O)O-heteroaryl, —C(O)O-substitutedheteroaryl, —C(O)O-heterocyclic, and —C(O)O-substituted heterocyclic,wherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl,substituted cycloalkenyl, aryl, substituted aryl, heteroaryl,substituted heteroaryl, heterocyclic, and substituted heterocyclic areas defined herein.

“(Carboxyl ester)oxy” or “carbonate” refers to the groups—O—C(O)O-alkyl, —O—C(O)O-substituted alkyl, —O—C(O)O-alkenyl,—O—C(O)O-substituted alkenyl, —O—C(O)O— alkynyl, —O—C(O)O-substitutedalkynyl, —O—C(O)O-aryl, —O—C(O)O-substituted aryl, —O—C(O)O— cycloalkyl,—O—C(O)O-substituted cycloalkyl, —O—C(O)O-cycloalkenyl,—O—C(O)O-substituted cycloalkenyl, —O—C(O)O-heteroaryl,—O—C(O)O-substituted heteroaryl, —O—C(O)O-heterocyclic, and—O—C(O)O-substituted heterocyclic, wherein alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic, andsubstituted heterocyclic are as defined herein.

“Cyano” or “nitrile” refers to the group —CN.

“Cycloalkyl” refers to cyclic alkyl groups of from 3 to 10 carbon atomshaving single or multiple cyclic rings including fused, bridged, andspiro ring systems. Examples of suitable cycloalkyl groups include, forinstance, adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyland the like. Such cycloalkyl groups include, by way of example, singlering structures such as cyclopropyl, cyclobutyl, cyclopentyl,cyclooctyl, and the like, or multiple ring structures such asadamantanyl, and the like.

The term “substituted cycloalkyl” refers to cycloalkyl groups havingfrom 1 to 5 substituents, or from 1 to 3 substituents, selected fromalkyl, substituted alkyl, alkoxy, substituted alkoxy, cycloalkyl,substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, acyl,acylamino, acyloxy, amino, substituted amino, aminoacyl, aminoacyloxy,oxyaminoacyl, azido, cyano, halogen, hydroxyl, oxo, thioketo, carboxyl,carboxylalkyl, thioaryloxy, thioheteroaryloxy, thioheterocyclooxy,thiol, thioalkoxy, substituted thioalkoxy, aryl, aryloxy, heteroaryl,heteroaryloxy, heterocyclyl, heterocyclooxy, hydroxyamino, alkoxyamino,nitro, —SO-alkyl, —SO-substituted alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryl and —SO₂-heteroaryl.

“Cycloalkenyl” refers to non-aromatic cyclic alkyl groups of from 3 to10 carbon atoms having single or multiple rings and having at least onedouble bond and preferably from 1 to 2 double bonds.

The term “substituted cycloalkenyl” refers to cycloalkenyl groups havingfrom 1 to 5 substituents, or from 1 to 3 substituents, selected fromalkoxy, substituted alkoxy, cycloalkyl, substituted cycloalkyl,cycloalkenyl, substituted cycloalkenyl, acyl, acylamino, acyloxy, amino,substituted amino, aminoacyl, aminoacyloxy, oxyaminoacyl, azido, cyano,halogen, hydroxyl, keto, thioketo, carboxyl, carboxylalkyl, thioaryloxy,thioheteroaryloxy, thioheterocyclooxy, thiol, thioalkoxy, substitutedthioalkoxy, aryl, aryloxy, heteroaryl, heteroaryloxy, heterocyclyl,heterocyclooxy, hydroxyamino, alkoxyamino, nitro, —SO-alkyl,—SO-substituted alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-aryl and —SO₂-heteroaryl.

“Cycloalkynyl” refers to non-aromatic cycloalkyl groups of from 5 to 10carbon atoms having single or multiple rings and having at least onetriple bond.

“Cycloalkoxy” refers to —O-cycloalkyl.

“Cycloalkenyloxy” refers to —O-cycloalkenyl.

“Halo” or “halogen” refers to fluoro, chloro, bromo, and iodo.

“Hydroxy” or “hydroxyl” refers to the group —OH.

“Heteroaryl” refers to an aromatic group of from 1 to 15 carbon atoms,such as from 1 to 10 carbon atoms and 1 to 10 heteroatoms selected fromthe group consisting of oxygen, nitrogen, and sulfur within the ring.Such heteroaryl groups can have a single ring (such as, pyridinyl,imidazolyl or furyl) or multiple condensed rings in a ring system (forexample as in groups such as, indolizinyl, quinolinyl, benzofuran,benzimidazolyl or benzothienyl), wherein at least one ring within thering system is aromatic and at least one ring within the ring system isaromatic, provided that the point of attachment is through an atom of anaromatic ring. In certain embodiments, the nitrogen and/or sulfur ringatom(s) of the heteroaryl group are optionally oxidized to provide forthe N-oxide (N→O), sulfinyl, or sulfonyl moieties. This term includes,by way of example, pyridinyl, pyrrolyl, indolyl, thiophenyl, andfuranyl. Unless otherwise constrained by the definition for theheteroaryl substituent, such heteroaryl groups can be optionallysubstituted with 1 to 5 substituents, or from 1 to 3 substituents,selected from acyloxy, hydroxy, thiol, acyl, alkyl, alkoxy, alkenyl,alkynyl, cycloalkyl, cycloalkenyl, substituted alkyl, substitutedalkoxy, substituted alkenyl, substituted alkynyl, substitutedcycloalkyl, substituted cycloalkenyl, amino, substituted amino,aminoacyl, acylamino, alkaryl, aryl, aryloxy, azido, carboxyl,carboxylalkyl, cyano, halogen, nitro, heteroaryl, heteroaryloxy,heterocyclyl, heterocyclooxy, aminoacyloxy, oxyacylamino, thioalkoxy,substituted thioalkoxy, thioaryloxy, thioheteroaryloxy, —SO-alkyl,—SO-substituted alkyl, —SO-aryl, —SO-heteroaryl, —SO₂— alkyl,—SO₂-substituted alkyl, —SO₂-aryl and —SO₂-heteroaryl, andtrihalomethyl.

The term “heteroaralkyl” refers to the groups -alkylene-heteroaryl wherealkylene and heteroaryl are defined herein. This term includes, by wayof example, pyridylmethyl, pyridylethyl, indolylmethyl, and the like.

“Heteroaryloxy” refers to —O-heteroaryl.

“Heterocycle,” “heterocyclic,” “heterocycloalkyl,” and “heterocyclyl”refer to a saturated or unsaturated group having a single ring ormultiple condensed rings, including fused bridged and spiro ringsystems, and having from 3 to 20 ring atoms, including 1 to 10 heteroatoms. These ring atoms are selected from the group consisting ofnitrogen, sulfur, or oxygen, wherein, in fused ring systems, one or moreof the rings can be cycloalkyl, aryl, or heteroaryl, provided that thepoint of attachment is through the non-aromatic ring. In certainembodiments, the nitrogen and/or sulfur atom(s) of the heterocyclicgroup are optionally oxidized to provide for the N-oxide, —S(O)—, or—SO₂— moieties.

Examples of heterocycles and heteroaryls include, but are not limitedto, azetidine, pyrrole, imidazole, pyrazole, pyridine, pyrazine,pyrimidine, pyridazine, indolizine, isoindole, indole, dihydroindole,indazole, purine, quinolizine, isoquinoline, quinoline, phthalazine,naphthylpyridine, quinoxaline, quinazoline, cinnoline, pteridine,carbazole, carboline, phenanthridine, acridine, phenanthroline,isothiazole, phenazine, isoxazole, phenoxazine, phenothiazine,imidazolidine, imidazoline, piperidine, piperazine, indoline,phthalimide, 1,2,3,4-tetrahydroisoquinoline,4,5,6,7-tetrahydrobenzo[b]thiophene, thiazole, thiazolidine, thiophene,benzo[b]thiophene, morpholinyl, thiomorpholinyl (also referred to asthiamorpholinyl), 1,1-dioxothiomorpholinyl, piperidinyl, pyrrolidine,tetrahydrofuranyl, and the like.

Unless otherwise constrained by the definition for the heterocyclicsubstituent, such heterocyclic groups can be optionally substituted with1 to 5, or from 1 to 3 substituents, selected from alkoxy, substitutedalkoxy, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, acyl, acylamino, acyloxy, amino, substituted amino,aminoacyl, aminoacyloxy, oxyaminoacyl, azido, cyano, halogen, hydroxyl,oxo, thioketo, carboxyl, carboxylalkyl, thioaryloxy, thioheteroaryloxy,thioheterocyclooxy, thiol, thioalkoxy, substituted thioalkoxy, aryl,aryloxy, heteroaryl, heteroaryloxy, heterocyclyl, heterocyclooxy,hydroxyamino, alkoxyamino, nitro, —SO-alkyl, —SO-substituted alkyl,—SO-aryl, —SO-heteroaryl, —SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryl,—SO₂-heteroaryl, and fused heterocycle.

“Heterocyclyloxy” refers to the group —O-heterocyclyl.

The term “heterocyclylthio” refers to the group heterocyclic-S—.

The term “heterocyclene” refers to the diradical group formed from aheterocycle, as defined herein.

The term “hydroxyamino” refers to the group —NHOH.

“Nitro” refers to the group —NO₂.

“Oxo” refers to the atom (═O).

“Sulfonyl” refers to the group SO₂-alkyl, SO₂-substituted alkyl,SO₂-alkenyl, SO₂-substituted alkenyl, SO₂-cycloalkyl, SO₂-substitutedcycloalkyl, SO₂-cycloalkenyl, SO₂-substituted cylcoalkenyl, SO₂-aryl,SO₂-substituted aryl, SO₂-heteroaryl, SO₂-substituted heteroaryl,SO₂-heterocyclic, and SO₂-substituted heterocyclic, wherein alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic, and substituted heterocyclic are as definedherein. Sulfonyl includes, by way of example, methyl-SO₂—, phenyl-SO₂—,and 4-methylphenyl-SO₂—.

“Sulfonyloxy” refers to the group —OSO₂-alkyl, OSO₂-substituted alkyl,OSO₂-alkenyl, OSO₂-substituted alkenyl, OSO₂-cycloalkyl,OSO₂-substituted cycloalkyl, OSO₂-cycloalkenyl, OSO₂-substitutedcylcoalkenyl, OSO₂-aryl, OSO₂-substituted aryl, OSO₂-heteroaryl,OSO₂-substituted heteroaryl, OSO₂-heterocyclic, and OSO₂ substitutedheterocyclic, wherein alkyl, substituted alkyl, alkenyl, substitutedalkenyl, alkynyl, substituted alkynyl, cycloalkyl, substitutedcycloalkyl, cycloalkenyl, substituted cycloalkenyl, aryl, substitutedaryl, heteroaryl, substituted heteroaryl, heterocyclic, and substitutedheterocyclic are as defined herein.

The term “aminocarbonyloxy” refers to the group —OC(O)NRR where each Ris independently hydrogen, alkyl, substituted alkyl, aryl, heteroaryl,or heterocyclic wherein alkyl, substituted alkyl, aryl, heteroaryl andheterocyclic are as defined herein.

“Thiol” refers to the group —SH.

“Thioxo” or the term “thioketo” refers to the atom (═S).

“Alkylthio” or the term “thioalkoxy” refers to the group —S-alkyl,wherein alkyl is as defined herein. In certain embodiments, sulfur maybe oxidized to —S(O)—. The sulfoxide may exist as one or morestereoisomers.

The term “substituted thioalkoxy” refers to the group —S-substitutedalkyl.

The term “thioaryloxy” refers to the group aryl-S— wherein the arylgroup is as defined herein including optionally substituted aryl groupsalso defined herein.

The term “thioheteroaryloxy” refers to the group heteroaryl-S— whereinthe heteroaryl group is as defined herein including optionallysubstituted aryl groups as also defined herein.

The term “thioheterocyclooxy” refers to the group heterocyclyl-S—wherein the heterocyclyl group is as defined herein including optionallysubstituted heterocyclyl groups as also defined herein.

In addition to the disclosure herein, the term “substituted,” when usedto modify a specified group or radical, can also mean that one or morehydrogen atoms of the specified group or radical are each, independentlyof one another, replaced with the same or different substituent groupsas defined below.

In addition to the groups disclosed with respect to the individual termsherein, substituent groups for substituting for one or more hydrogens(any two hydrogens on a single carbon can be replaced with ═O, ═NR⁷⁰,═N—OR⁷⁰, ═N₂ or ═S) on saturated carbon atoms in the specified group orradical are, unless otherwise specified, —R⁶⁰, halo, ═O, —OR⁷⁰, —SR⁷⁰,—NR⁸⁰R⁸⁰, trihalomethyl, —CN, —OCN, —SCN, —NO, —NO₂, ═N₂, —N₃, —SO₂R⁷⁰,—SO₂O⁻M⁺, —SO₂OR⁷⁰, —OSO₂R⁷⁰, —OSO₂O⁻M⁺, —OSO₂OR⁷⁰, —P(O)(O⁻)₂(M⁺)₂,—P(O)(OR⁷⁰)O⁻M⁺, —P(O)(OR⁷⁰)₂, —C(O)R⁷⁰, —C(S)R⁷⁰, —C(NR⁷⁰)R⁷⁰,—C(O)O⁻M⁺, —C(O)OR⁷⁰, —C(S)OR⁷⁰, —C(O)NR⁸⁰R⁸⁰, —C(NR⁷⁰)NR⁸⁰R⁸⁰,—OC(O)R⁷⁰, —OC(S)R⁷⁰, —OC(O)O⁻M⁺, —OC(O)OR⁷⁰, —OC(S)OR⁷⁰. —NR⁷⁰C(O)R⁷⁰,—NR⁷⁰C(S)R⁷⁰, —NR⁷⁰CO₂ ⁻M⁺, —NR⁷⁰CO₂R⁷⁰, —NR⁷⁰C(S)OR⁷⁰,—NR⁷⁰C(O)NR⁸⁰R⁸⁰, —NR⁷⁰C(NR⁷⁰)R⁷⁰ and —NR⁷⁰C(NR⁷⁰)NR⁸⁰R⁸⁰, where R⁶⁰ isselected from the group consisting of optionally substituted alkyl,cycloalkyl, heteroalkyl, heterocycloalkylalkyl, cycloalkylalkyl, aryl,arylalkyl, heteroaryl and heteroarylalkyl, each R⁷⁰ is independentlyhydrogen or R⁶⁰; each R⁸⁰ is independently R⁷⁰ or alternatively, twoR⁸⁰, taken together with the nitrogen atom to which they are bonded,form a 5-, 6- or 7-membered heterocycloalkyl which may optionallyinclude from 1 to 4 of the same or different additional heteroatomsselected from the group consisting of O, N and S, of which N may have —Hor C₁-C₃ alkyl substitution; and each M⁺ is a counter ion with a netsingle positive charge. Each M⁺ may independently be, for example, analkali ion, such as K⁺, Na⁺, Li⁺; an ammonium ion, such as ⁺N(R⁶⁰)₄; oran alkaline earth ion, such as [Ca²⁺]_(0.5), [Mg²⁺]_(0.5), or[Ba²⁺]_(0.5) (“subscript 0.5 means that one of the counter ions for suchdivalent alkali earth ions can be an ionized form of a compound of theinvention and the other a typical counter ion such as chloride, or twoionized compounds disclosed herein can serve as counter ions for suchdivalent alkali earth ions, or a doubly ionized compound of theinvention can serve as the counter ion for such divalent alkali earthions). As specific examples, —NR⁸⁰R⁸⁰ is meant to include —NH₂,—NH-alkyl, N-pyrrolidinyl, N-piperazinyl, 4N-methyl-piperazin-1-yl andN-morpholinyl.

In addition to the disclosure herein, substituent groups for hydrogenson unsaturated carbon atoms in “substituted” alkene, alkyne, aryl andheteroaryl groups are, unless otherwise specified, —R⁶⁰, halo, —O⁻M⁺,—OR⁷⁰, —SR⁷⁰, —S⁻M⁺, —NR⁸⁰R⁸⁰, trihalomethyl, —CF₃, —CN, —OCN, —SCN,—NO, —NO₂, —N₃, —SO₂R⁷⁰, —SO₃ ⁻M⁺, —SO₃R⁷⁰, —OSO₂R⁷⁰, —OSO₃ ⁻M⁺,—OSO₃R⁷⁰, —PO₃ ⁻² (M⁺)₂, —P(O)(OR⁷⁰)O⁻M⁺, —P(O)(OR⁷⁰)₂, —C(O)R⁷⁰,—C(S)R⁷⁰, —C(NR⁷⁰)R⁷⁰, —CO₂ ⁻M⁺, —CO₂R⁷⁰, —C(S)OR⁷⁰, —C(O)NR⁸⁰R⁸⁰,—C(NR⁷⁰)NR⁸⁰R⁸⁰, —OC(O)R⁷⁰, —OC(S)R⁷⁰, —OCO₂ ⁻M⁺, —OCO₂R⁷⁰, —OC(S)OR⁷⁰,—NR⁷⁰C(O)R⁷⁰, —NR⁷⁰C(S)R⁷⁰, —NR⁷⁰CO₂ ⁻M⁺, —NR⁷⁰CO₂R⁷⁰, —NR⁷⁰C(S)OR⁷⁰,—NR⁷⁰C(O)NR⁸⁰R⁸⁰, —NR⁷⁰C(NR⁷⁰)R⁷⁰ and —NR⁷⁰C(NR⁷⁰)NR⁸⁰R⁸⁰, where R⁶⁰,R⁷⁰, R⁸⁰ and M⁺ are as previously defined, provided that in case ofsubstituted alkene or alkyne, the substituents are not —O⁻M⁺, —OR⁷⁰,—SR⁷⁰, or —S⁻M⁺.

In addition to the groups disclosed with respect to the individual termsherein, substituent groups for hydrogens on nitrogen atoms in“substituted” heteroalkyl and cycloheteroalkyl groups are, unlessotherwise specified, —R⁶⁰, —O⁻M⁺, —OR⁷⁰, —SR⁷⁰, —S⁻M⁺, —NR⁸⁰R⁸⁰,trihalomethyl, —CF₃, —CN, —NO, —NO₂, —S(O)₂R⁷⁰, —S(O)₂O⁻M⁺, —S(O)₂OR⁷⁰,—OS(O)₂R⁷⁰, —OS(O)₂O⁻M⁺, —OS(O)₂OR⁷⁰, —P(O)(O⁻)₂(M⁺)₂, —P(O)(OR⁷⁰)O⁻M⁺,—P(O)(OR⁷⁰)(OR⁷⁰), —C(O)R⁷⁰, —C(S)R⁷⁰, —C(NR⁷⁰)R⁷⁰, —C(O)OR⁷⁰,—C(S)OR⁷⁰, —C(O)NR⁸⁰R⁸⁰, —C(NR⁷⁰)NR⁸⁰R⁸⁰, —OC(O)R⁷⁰, —OC(S)R⁷⁰,—OC(O)OR⁷⁰, —OC(S)OR⁷⁰, —NR⁷⁰C(O)R⁷⁰, —NR⁷⁰C(S)R⁷⁰, —NR⁷⁰C(O)OR⁷⁰,—NR⁷⁰C(S)OR⁷⁰, —NR⁷⁰C(O)NR⁸⁰R⁸⁰, —NR⁷⁰C(NR⁷⁰)R⁷⁰ and—NR⁷⁰C(NR⁷⁰)NR⁸⁰R⁸⁰, where R⁶⁰, R⁷⁰, R⁸⁰ and M⁺ are as previouslydefined.

In addition to the disclosure herein, in a certain embodiment, a groupthat is substituted has 1, 2, 3, or 4 substituents, 1, 2, or 3substituents, 1 or 2 substituents, or 1 substituent.

It is understood that in all substituted groups defined above, polymersarrived at by defining substituents with further substituents tothemselves (e.g., substituted aryl having a substituted aryl group as asubstituent which is itself substituted with a substituted aryl group,which is further substituted by a substituted aryl group, etc.) are notintended for inclusion herein. In such cases, the maximum number of suchsubstitutions is three. For example, serial substitutions of substitutedaryl groups specifically contemplated herein are limited to substitutedaryl-(substituted aryl)-substituted aryl.

Unless indicated otherwise, the nomenclature of substituents that arenot explicitly defined herein are arrived at by naming the terminalportion of the functionality followed by the adjacent functionalitytoward the point of attachment. For example, the substituent“arylalkyloxycarbonyl” refers to the group (aryl)-(alkyl)-O—C(O)—.

As to any of the groups disclosed herein which contain one or moresubstituents, it is understood, of course, that such groups do notcontain any substitution or substitution patterns which are stericallyimpractical and/or synthetically non-feasible. In addition, the subjectcompounds include all stereochemical isomers arising from thesubstitution of these compounds.

The term “pharmaceutically acceptable salt” means a salt which isacceptable for administration to a patient, such as a mammal (salts withcounterions having acceptable mammalian safety for a given dosageregime). Such salts can be derived from pharmaceutically acceptableinorganic or organic bases and from pharmaceutically acceptableinorganic or organic acids. “Pharmaceutically acceptable salt” refers topharmaceutically acceptable salts of a compound, which salts are derivedfrom a variety of organic and inorganic counter ions well known in theart and include, by way of example only, sodium, potassium, calcium,magnesium, ammonium, tetraalkylammonium, and the like; and when themolecule contains a basic functionality, salts of organic or inorganicacids, such as hydrochloride, hydrobromide, formate, tartrate, besylate,mesylate, acetate, maleate, oxalate, and the like.

The term “salt thereof” means a compound formed when a proton of an acidis replaced by a cation, such as a metal cation or an organic cation andthe like. Where applicable, the salt is a pharmaceutically acceptablesalt, although this is not required for salts of intermediate compoundsthat are not intended for administration to a patient. By way ofexample, salts of the present compounds include those wherein thecompound is protonated by an inorganic or organic acid to form a cation,with the conjugate base of the inorganic or organic acid as the anioniccomponent of the salt.

“Solvate” refers to a complex formed by combination of solvent moleculeswith molecules or ions of the solute. The solvent can be an organiccompound, an inorganic compound, or a mixture of both. Some examples ofsolvents include, but are not limited to, methanol,N,N-dimethylformamide, tetrahydrofuran, dimethylsulfoxide, and water.When the solvent is water, the solvate formed is a hydrate.

“Stereoisomer” and “stereoisomers” refer to compounds that have sameatomic connectivity but different atomic arrangement in space.Stereoisomers include cis-trans isomers, E and Z isomers, enantiomers,and diastereomers.

“Tautomer” refers to alternate forms of a molecule that differ only inelectronic bonding of atoms and/or in the position of a proton, such asenol-keto and imine-enamine tautomers, or the tautomeric forms ofheteroaryl groups containing a —N═C(H)—NH— ring atom arrangement, suchas pyrazoles, imidazoles, benzimidazoles, triazoles, and tetrazoles. Aperson of ordinary skill in the art would recognize that othertautomeric ring atom arrangements are possible.

It will be appreciated that the term “or a salt or solvate orstereoisomer thereof” is intended to include all permutations of salts,solvates and stereoisomers, such as a solvate of a pharmaceuticallyacceptable salt of a stereoisomer of subject compound.

“Pharmaceutically effective amount” and “therapeutically effectiveamount” refer to an amount of a compound sufficient to treat a specifieddisorder or disease or one or more of its symptoms and/or to prevent theoccurrence of the disease or disorder. In reference to tumorigenicproliferative disorders, a pharmaceutically or therapeutically effectiveamount comprises an amount sufficient to, among other things, cause thetumor to shrink or decrease the growth rate of the tumor.

“Patient” refers to human and non-human subjects, especially mammaliansubjects.

The term “treating” or “treatment” as used herein means the treating ortreatment of a disease or medical condition in a patient, such as amammal (particularly a human) that includes: (a) preventing the diseaseor medical condition from occurring, such as, prophylactic treatment ofa subject; (b) ameliorating the disease or medical condition, such as,eliminating or causing regression of the disease or medical condition ina patient; (c) suppressing the disease or medical condition, for exampleby, slowing or arresting the development of the disease or medicalcondition in a patient; or (d) alleviating a symptom of the disease ormedical condition in a patient.

REPRESENTATIVE EMBODIMENTS

The following substituents and values are intended to providerepresentative examples of various aspects and embodiments. Theserepresentative values are intended to further define and illustrate suchaspects and embodiments and are not intended to exclude otherembodiments or to limit the scope of the present disclosure. In thisregard, the representation that a particular value or substituent ispreferred is not intended in any way to exclude other values orsubstituents from the present disclosure unless specifically indicated.

These compounds may contain one or more chiral centers and therefore,the embodiments are directed to racemic mixtures; pure stereoisomers(i.e., enantiomers or diastereomers); stereoisomer-enriched mixtures andthe like unless otherwise indicated. When a particular stereoisomer isshown or named herein, it will be understood by those skilled in the artthat minor amounts of other stereoisomers may be present in thecompositions unless otherwise indicated, provided that the desiredutility of the composition as a whole is not eliminated by the presenceof such other isomers.

The compositions of the present disclosure include compounds of theformulae shown below. Pharmaceutical compositions and methods of thepresent disclosure also contemplate compounds of the following formulae.

Formula A

Embodiments of the compounds are represented by the following formula(A):

wherein either Y¹ is X^(a) and Y² is hydrogen, or Y² is X^(a) and Y¹ ishydrogen;

wherein X^(a) is selected from carboxylic acid, carboxyl ester,heterocyclyl, substituted heterocyclyl, heteroaryl and substitutedheteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (A);

or a salt or stereoisomer thereof.

Formulae (Ia) and (Ib)

In some embodiments of formula (A), the compounds are represented byformula (Ia) or (Ib):

wherein

X^(a) is selected from carboxylic acid, carboxyl ester, heterocyclyl,substituted heterocyclyl, heteroaryl and substituted heteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (Ia) or (Ib);

or a salt or stereoisomer thereof.

Embodiments of the present disclosure include a compound of formula(Ia):

wherein

X^(a) is selected from carboxylic acid, carboxyl ester, heterocyclyl,substituted heterocyclyl, heteroaryl and substituted heteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —R¹⁵,

or a salt or stereoisomer thereof.

Embodiments of the present disclosure include a compound of formula(Ib):

wherein

X^(a) is selected from carboxylic acid, carboxyl ester, heterocyclyl,substituted heterocyclyl, heteroaryl and substituted heteroaryl; and

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —R¹⁵,

or a salt or stereoisomer thereof.

In some embodiments of formulae (Ia) and (Ib), the compound is a dimer,where R¹⁵ includes a linking group and a compound of formulae (Ia) or(Ib). In certain embodiments, the compound is a symmetrical dimer. Incertain embodiments, the compound is an unsymmetrical dimer. In someinstances of formulae (Ia) and (Ib), R¹⁵ includes a linking group and acompound of formula (Ia). In some instances of formulae (Ia) and (Ib),R¹⁵ includes a linking group and a compound of formula (Ib).

In certain embodiments, X^(a) is selected from carboxylic acid, carboxylester, heterocyclyl, substituted heterocyclyl, heteroaryl andsubstituted heteroaryl. In certain embodiments, X^(a) is a carboxylicacid. In certain embodiments, X^(a) is a carboxyl ester. In certainembodiments, X^(a) is heterocyclyl or substituted heterocyclyl. Incertain embodiments, X^(a) is heteroaryl or substituted heteroaryl.

In certain embodiments, X^(a) is a heterocyclyl or a heteroaryl asdescribed above. In certain embodiments, the heterocyclyl or heteroaryldescribed above is substituted with one or more substituents. Forexample, in certain embodiments, the substituent on X^(a) is a C₁₋₆alkyl or a progroup. In certain embodiments, the substituent on X^(a) isC₁₋₆ alkyl. In certain embodiments, the substituent on X^(a) is methyl.In certain embodiments, the substituent on X^(a) is ethyl. In certainembodiments, the substituent on X^(a) is propyl. In certain embodiments,the substituent on X^(a) is butyl. In certain embodiments, thesubstituent on X^(a) is pentyl. In certain embodiments, the substituenton X^(a) is hexyl. The C₁₋₆ alkyl may be unbranched or branched. Forexample, the substituent on X¹ may be propyl, such as n-propyl oriso-propyl. For example, the substituent on X¹ may be butyl, such asn-butyl, sec-butyl (1-methylpropyl), iso-butyl (2-methylpropyl) ortert-butyl (1,1-dimethylethyl).

In certain embodiments, the substituent on X^(a) is a progroup. Forexample, the compounds described herein can be provided in prodrug form.“Prodrug” refers to a derivative of an active compound (e.g., a drug)that undergoes a transformation under the conditions of use, such aswithin the body, to release the active compound. Prodrugs may be, butare not necessarily, pharmacologically inactive until converted into theactive drug. Prodrugs may be obtained by masking a functional group inthe drug believed to be in part required for activity with a progroup toform a promoiety which undergoes a transformation, such as cleavage,under the specified conditions of use to release the functional group,and hence the active drug. The cleavage of the promoiety can proceedspontaneously, such as by way of a hydrolysis reaction, or it can becatalyzed or induced by another agent, such as by an enzyme, by light,by acid, or by a change of or exposure to a physical or environmentalparameter, such as a change of temperature. The agent can be endogenousto the conditions of use, such as an enzyme present in the cells towhich the prodrug is administered or the acidic conditions of thestomach, or it can be supplied exogenously. In certain cases, compoundsthat include a progroup may facilitate an increase in gastrointestinalpermeability, an increase in gastrointestinal absorption, and/or anincrease in solubility of the compound. In certain cases, compounds thatinclude a progroup may facilitate removal of the progroup at a desiredsite of action for the pharmaceutically active form of the compound, orafter a desired amount of time after administration of the compound(e.g., delayed release formulations, controlled release formulations,and the like). A wide variety of progroups, as well as the resultantpromoieties, suitable for masking functional groups in the active drugsto yield prodrugs may be used. For example, a hydroxyl functional groupcan be masked as a sulfonate, ester or carbonate promoiety, which can behydrolyzed in vivo to provide the hydroxyl group. An amino functionalgroup can be masked as an amide, carbamate, imine, urea, phosphenyl,phosphoryl or sulfenyl promoiety, which can be hydrolyzed in vivo toprovide the amino group. A carboxyl group can be masked as an ester(including silyl esters and thioesters), amide or hydrazide promoiety,which can be hydrolyzed in vivo to provide the carboxyl group. Specificexamples of suitable progroups and their respective promoieties will beapparent to those of skill in the art. Embodiments of progroupsaccording to the present disclosure are also described in more detailbelow.

In certain embodiments, X^(a) is a heterocyclyl or a heteroaryl asdescribed above. Examples of heterocyclyl and heteroaryl groups include,but are not limited to, oxazole, oxadiazole (e.g., 1,2,3-oxadiazole,1,3,4-oxadiazole, 1,2,4-oxadiazole), tetrazole, tetrazolone, thiazole,thiadiazole (e.g., 1,2,3-thiadiazole, 1,3,4-thiadiazole,1,2,4-thiadiazole), and the like. In certain embodiments, thesubstituent on X^(a) may be X¹ as described in more detail belowregarding compounds of formula (IIa) and (IIb). For example, compoundsof formula (Ia) may be selected from the following compounds:

wherein X¹ and R¹ are as described below regarding compounds of formulae(Ia), (Ib), (IIa) and (IIb).

In some embodiments, compounds of formula (Ib) may be selected from thefollowing compounds:

wherein X¹ and R¹ are as described below regarding compounds of formulae(Ia), (b), (IIa) and (IIb).

In certain embodiments, R¹ is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, and —R¹⁵.

In certain embodiments, R¹ is hydrogen. In certain embodiments, R¹ isalkyl or substituted alkyl. In certain embodiments, R¹ is alkenyl orsubstituted alkenyl. In certain embodiments, R¹ is alkynyl orsubstituted alkynyl. In certain embodiments, R¹ is cycloalkyl orsubstituted cycloalkyl. In certain embodiments, R¹ is cyclohexyl orsubstituted cyclohexyl. In certain embodiments, R¹ is cyclopentyl orsubstituted cyclopentyl. In certain embodiments, R¹ is cyclobutyl orsubstituted cyclobutyl. In certain embodiments, R¹ is cyclopropyl orsubstituted cyclopropyl. In certain embodiments, R¹ is heterocyclyl orsubstituted heterocyclyl. In certain embodiments, R¹ is4-tetrahydropyranyl or substituted 4-tetrahydropyranyl. In certainembodiments, R¹ is aryl or substituted aryl. In certain embodiments, R¹is phenyl or substituted phenyl. In certain embodiments, R¹ isheteroaryl or substituted heteroaryl. In certain embodiments, R¹ ispyridyl or substituted pyridyl. In certain embodiments, R¹ is a2-pyridyl, a 3-pyridyl or 4-pyridyl. In certain embodiments, R¹ is asubstituted 2-pyridyl, a substituted 3-pyridyl or a substituted4-pyridyl.

In certain embodiments, R¹ is a substituted alkenyl. In certainembodiments, the compound is of one of the following formulae:

wherein each X^(a) is as described above; or a salt or stereoisomerthereof.

In certain embodiments, R¹ is a substituted alkenyl. In certainembodiments, the compound is of one of the following formulae:

wherein each X^(a) is as described above, or a salt or stereoisomerthereof. In certain embodiments, the compound is a symmetrical dimer andeach X^(a) is the same. In some instances, the compound is anunsymmetrical dimer where each X^(a) is different.

In certain embodiments of the compounds according to formula (Ia) or(Ib), R¹ is derived from an amino acid. In some cases, R¹ can have theformula:

wherein R^(a) is an amino acid side chain, e.g., —H for glycine, —CH₃for alanine, and each R^(b) is independently selected from H, C₁₋₆alkyl, and —C(O)C₁₋₆ alkyl. For example, such compounds can have one ofthe following formulae:

wherein R^(a) is an amino acid side chain, e.g., —H for glycine, —CH₃for alanine, and each R^(b) is independently selected from H, C₁₋₆alkyl, and —C(O)C₁₋₆ alkyl. Other examples of R¹ groups derived fromamino acids include compounds of one of the following formulae:

derived from serine, wherein each R^(b) is independently selected fromH, C₁₋₆ alkyl, and —C(O)C₁₋₆ alkyl and R^(c) is selected from H and C₁₋₆alkyl.

In certain embodiments of the compounds according to formula (Ia) or(Ib), R¹ can have the formula:

wherein R^(d) and R^(d′) are independently selected from H and C₁₋₆alkyl.

An amino acid side chain includes side chains commonly found innaturally occurring amino acids (e.g., Ala or A, Cys or C, Asp or D, Gluor E, Phe or F, Gly or G, His or H, Ile or I, Lys or K, Leu or L, Met orM, Asn or N, Pro or P, Gln or Q, Arg or R, Ser or S, Thr or T, Val or V,Trp or W, Tyr or Y). Amino acid side chains may also include side chainfound in amino acid analogs or unnatural amino acids. The terms “aminoacid analog,” “unnatural amino acid,” and the like may be usedinterchangeably, and include amino acid-like compounds that are similarin structure and/or overall shape to one or more amino acids commonlyfound in naturally occurring proteins. Amino acid analogs also includenatural amino acids with modified side chains or backbones. Amino acidanalogs also include amino acid analogs with the same stereochemistry asin the naturally occurring D-form, as well as the L-form of amino acidanalogs.

In certain embodiments, R¹ is alkyl, such as C₁₋₆ alkyl. In certainembodiments, R¹ is methyl. In certain embodiments, R¹ is ethyl. Incertain embodiments, R¹ is propyl. In certain embodiments, R¹ is butyl.In certain embodiments, R¹ is pentyl. In certain embodiments, R¹ ishexyl. The C₁₋₆ alkyl may be unbranched or branched. For example, R¹ maybe propyl, such as n-propyl or iso-propyl. For example, R¹ may be butyl,such as n-butyl, sec-butyl (1-methylpropyl), iso-butyl (2-methylpropyl)or tert-butyl (1,1-dimethylethyl).

In certain embodiments, R¹ is substituted alkyl, such as substitutedC₁₋₆ alkyl. In certain embodiments, R¹ is substituted methyl. In certainembodiments, R¹ is substituted ethyl. In certain embodiments, R¹ issubstituted propyl. In certain embodiments, R¹ is substituted butyl. Incertain embodiments, R¹ is substituted pentyl. In certain embodiments,R¹ is substituted hexyl. Substituents on R¹ include, but are not limitedto, halogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl,alkynyl, substituted alkynyl, alkoxy, substituted alkoxy, hydroxyl,carboxyl, carboxyl ester, amino, substituted amino, acyl, aminoacyl,acylamino, thioalkoxy, sulfonyl, aminosulfonyl, sulfonylamino,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. For example, R¹ may be a substituted alkyl (e.g.,substituted C₁₋₆ alkyl), substituted by a hydroxyl. In some instances,R¹ is a substituted alkyl (e.g., substituted C₁₋₆ alkyl), substituted byalkoxy or substituted alkoxy, such as a C₁₋₆ alkoxy or a C₁₋₆substituted alkoxy. In some instances, R¹ is a substituted alkyl (e.g.,substituted C₁₋₆ alkyl), substituted by amino or substituted amino. Insome instances, R¹ is a substituted alkyl (e.g., substituted C₁₋₆alkyl), substituted by carboxyl or carboxyl ester. In some instances, R¹is a substituted alkyl (e.g., substituted C₁₋₆ alkyl), substituted byaminoacyl or acylamino. In some instances, R¹ is a substituted alkyl(e.g., substituted C₁₋₆ alkyl), substituted by thioalkoxy or sulfonyl.In some instances, R¹ is a substituted alkyl (e.g., substituted C₁₋₆alkyl), substituted by cycloalkyl or substituted cycloalkyl, such as,for example, C₃₋₈ cycloalkyl or C₃₋₈ substituted cycloalkyl, or C₃₋₆cycloalkyl or C₃₋₆ substituted cycloalkyl, or C₃₋₅ cycloalkyl or C₃₋₅substituted cycloalkyl, or C₃₋₄ cycloalkyl or C₃₋₄ substitutedcycloalkyl. In some instances, R¹ is a substituted alkyl (e.g.,substituted C₁₋₆ alkyl), substituted by heterocyclyl or substitutedheterocyclyl, such as, for example, C₃₋₈ heterocyclyl or C₃₋₈substituted heterocyclyl, or C₃₋₆ heterocyclyl or C₃₋₆ substitutedheterocyclyl, or C₃₋₅ heterocyclyl or C₃₋₅ substituted heterocyclyl, orC₃₋₄ heterocyclyl or C₃₋₄ substituted heterocyclyl. In some instances,R¹ is a substituted alkyl (e.g., substituted C₁₋₆ alkyl), substituted byaryl or substituted aryl, such as, for example, C₃₋₆ aryl or C₃₋₆substituted aryl, such as phenyl or substituted phenyl. In someinstances, R¹ is a substituted alkyl (e.g., substituted C₁₋₆ alkyl),substituted by heteroaryl or substituted heteroaryl, such as, forexample, C₃₋₆ heteroaryl or C₃₋₆ substituted heteroaryl. Combinations ofthe above substituents on R¹ are also included. Any of the R¹ groupsdescribed herein may be included in the compounds of formulae (Ia) or(Ib).

For example, in certain embodiments, R¹ is alkyl, substituted alkyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, or substitutedheteroaryl, such that the compound of formula (Ia) has a structureselected from the following:

wherein

X^(a) is as described above;

each R is independently selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, sulfoxy and phosphate; and

n is 0, 1, 2, 3, 4 or 5;

or a salt or stereoisomer thereof.

For example, in certain embodiments, R¹ is alkyl, substituted alkyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, or substitutedheteroaryl, such that the compound of formula (Ia) has a structureselected from the following:

wherein

X^(a) is as described above;

each R is independently selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, sulfoxy and phosphate; and

n is 0, 1, 2, 3, 4 or 5;

or a salt or stereoisomer thereof.

In certain embodiments, each R is independently selected from hydrogen,alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, cycloalkyl, substituted cycloalkyl, heterocyclyl,substituted heterocyclyl, aryl, substituted aryl, heteroaryl, andsubstituted heteroaryl. In certain embodiments, R is hydrogen. Incertain embodiments, R is alkyl or substituted alkyl, such as C₁₋₆ alkyl(e.g., methyl, ethyl, propyl, butyl, pentyl, or hexyl) or C₁₋₆substituted alkyl. In certain embodiments, R is alkenyl or substitutedalkenyl. In certain embodiments, R is alkynyl or substituted alkynyl. Incertain embodiments, R is cycloalkyl or substituted cycloalkyl, such asC₃₋₈ cycloalkyl or C₃₋₈ substituted cycloalkyl, or C₃₋₆ cycloalkyl orC₃₋₆ substituted cycloalkyl, or C₃₋₅ cycloalkyl or C₃₋₅ substitutedcycloalkyl. In certain embodiments, R is heterocyclyl or substitutedheterocyclyl, such as C₃₋₈ heterocyclyl or C₃₋₈ substitutedheterocyclyl, or C₃₋₆ heterocyclyl or C₃₋₆ substituted heterocyclyl, orC₃₋₅ heterocyclyl or C₃₋₅ substituted heterocyclyl. In certainembodiments, R is aryl or substituted aryl, such as C₃₋₈ aryl or C₃₋₈substituted aryl, or C₃₋₆ aryl or C₃₋₆ substituted aryl (e.g., phenyl orsubstituted phenyl). In certain embodiments, R is heteroaryl orsubstituted heteroaryl, such as C₃₋₈ heteroaryl or C₃₋₈ substitutedheteroaryl, or C₃₋₆ heteroaryl or C₃₋₆ substituted heteroaryl. Inparticular embodiments, R is —P(O)(OH)₂ or a salt thereof, and in otherembodiments, R is —S(O)₂OH or a salt thereof.

In some embodiments, the compound is a dimer. In these embodiments, R¹is R⁵, where R¹⁵ includes a linking group and a second compound offormula (Ia) or (Ib). By “linking group” is meant a moiety that connectstwo or more moieties together through one or more covalent bonds andatoms. In certain embodiments, the linking group is an alkyl linkinggroup, such as a C₁₋₁₀ alkyl linking group, or a C₁₋₈ alkyl linkinggroup, or a C₁₋₆ alkyl linking group, or a C₁₋₃ alkyl linking group. Incertain embodiments, the linking group attaches a first compound offormula (Ia) or (Ib) to a second compound of formula (Ia) or (Ib). Insome instances, the first compound of formula (Ia) or (Ib) has one endof the linking group attached at the R¹ position, and the other end ofthe linking group is attached at the R¹ position of the second compoundof formula (Ia) or (Ib). In these embodiments, the two compounds offormulae (Ia) and/or (Ib) in the dimer are connected to each other attheir respective R¹ positions through the linking group.

In certain embodiments, the linking group is has the structure:—(CH₂)_(n)—Z_(y)—(CH₂)_(m)—, wherein

n is an integer from 1 to 6;

m is 0 or an integer from 1 to 6;

y is 0 or 1; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—.

In certain embodiments, n is an integer from 1 to 6, such as 1, 2, 3, 4,5 or 6.

In certain embodiments, m is 0 or an integer from 1 to 6. In certainembodiments, m is 0, and thus the —(CH₂)_(m)— portion of the linkinggroup is not present. In certain embodiments, m is an integer from 1 to6, such as 1, 2, 3, 4, 5 or 6.

In certain embodiments, y is 0 or 1. In certain embodiments, y is 0, andthus Z is not present. In certain embodiments, y is 1, and thus Z ispresent.

In certain embodiments, Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or—O—S(O)₂—O—. In certain embodiments, Z is O. In certain embodiments, Zis NH. In certain embodiments, Z is —O—P(O)(OH)—O—. In certainembodiments, Z is S. In certain embodiments, Z is S(O). In certainembodiments, Z is SO₂. In certain embodiments, Z is —O—S(O)₂—O—.

In certain embodiments, n is 1, m is 0 and y is 0. In certainembodiments, n is 2, m is 0 and y is 0. In certain embodiments, n is 3,m is 0 and y is 0. In certain embodiments, n is 4, m is 0 and y is 0. Incertain embodiments, n is 5, m is 0 and y is 0. In certain embodiments,n is 6, m is 0 and y is 0.

In certain embodiments, n is 1, m is 1, y is 1 and Z is O. In certainembodiments, n is 2, m is 2, y is 1 and Z is O. In certain embodiments,n is 1, m is 1, y is 1 and Z is NH. In certain embodiments, n is 2, m is2, y is 1 and Z is NH. In certain embodiments, n is 1, m is 1, y is 1and Z is —O—P(O)(OH)—O—. In certain embodiments, n is 2, m is 2, y is 1and Z is —O—P(O)(OH)—O—. In certain embodiments, n is 1, m is 1, y is 1and Z is S. In certain embodiments, n is 2, m is 2, y is 1 and Z is S.In certain embodiments, n is 1, m is 1, y is 1 and Z is S(O). In certainembodiments, n is 2, m is 2, y is 1 and Z is S(O). In certainembodiments, n is 1, m is 1, y is 1 and Z is SO₂. In certainembodiments, n is 2, m is 2, y is 1 and Z is SO₂. In certainembodiments, n is 1, m is 1, y is 1 and Z is —O—S(O)₂—O—. In certainembodiments, n is 2, m is 2, y is 1 and Z is —O—S(O)₂—O—.

In certain embodiments, n is 1, m is 1, and y is 1. As such, in certainembodiments, the compound has the formula:

wherein

X^(a′) and X^(a″) are each independently X^(a); and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—, or a salt orstereoisomer thereof.

In certain embodiments, n is 1, m is 1, and y is 1. As such, in certainembodiments, the compound has the formula:

wherein

X^(a′) and X^(a″) are each independently X^(a); and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, n is 1, m is 1, and y is 1. As such, in certainembodiments, the compound has the formula:

wherein

X^(a′) and X^(a)″ are each independently X^(a); and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, n is 2, m is 2, and y is 1. As such, in certainembodiments, the compound has the formula:

wherein

X^(a′) and X^(a″) are each independently X^(a); and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein

X^(a′) and X^(a″) are each independently X^(a); and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein

X^(a′) and X^(a″) are each independently X^(a); and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, X^(a′) and X^(a″) are each independently X^(a)as described above. In certain embodiments, X^(a′) and X^(a″) are thesame. In certain embodiments, X^(a′) and X^(a″) are different. Forexample, X^(a′) and X^(a″) may each be independently selected fromcarboxyl ester, heterocyclyl, substituted heterocyclyl, heteroaryl andsubstituted heteroaryl. In certain embodiments, X^(a′) is a carboxylester. In certain embodiments, X^(a′) is heterocyclyl or substitutedheterocyclyl. In certain embodiments, X^(a′) is heteroaryl orsubstituted heteroaryl. In certain embodiments, X^(a″) is a carboxylester. In certain embodiments, X^(a″) is heterocyclyl or substitutedheterocyclyl. In certain embodiments, X^(a″) is heteroaryl orsubstituted heteroaryl.

In certain embodiments, X^(a′) is a heterocyclyl or a heteroaryl asdescribed above. In certain embodiments, the heterocyclyl or heteroarylis substituted with one or more substituents. For example, in certainembodiments, the substituent on X^(a′) may be X¹, such as a C₁₋₆ alkylor a progroup as described in more detail below regarding compounds offormulae (IIa) and (IIb).

In certain embodiments, X^(a″) is a heterocyclyl or a heteroaryl asdescribed above. In certain embodiments, the heterocyclyl or heteroarylis substituted with one or more substituents. For example, in certainembodiments, the substituent on X^(a″) may be X¹, such as a C₁₋₆ alkylor a progroup as described in more detail below regarding compounds offormulae (IIa) and (IIb).

In certain embodiments, Z is O, —O—P(O)(OH)—O—, NH, S, S(O), SO₂ or—O—S(O)₂—O—. In certain embodiments, Z is O. In certain embodiments, Zis NH. In certain embodiments, Z is —O—P(O)(OH)—O—. In certainembodiments, Z is S. In certain embodiments, Z is S(O). In certainembodiments, Z is SO₂. In certain embodiments, Z is —O—S(O)₂—O—.

In certain embodiments, the compound of formula (Ia) is a dimer selectedfrom the following compounds:

wherein X^(a′) and X^(a′) are as described above, or a salt orstereoisomer thereof.

In certain embodiments where the compound is a dimer, the compound maybe a dimer prodrug. In these embodiments, the linking group connectingthe two compounds of formula (Ia) and/or (Ib) in the dimer may be acleavable linking group. By “cleavable” is meant that one or morecovalent bonds in the linking group may be broken. In some instances,cleavage of the linking group in the dimer releases the active agentmoieties (e.g., two pharmaceutically active compounds). For example, acleavable linking group may be cleaved by hydrolysis of one or morebonds in the linking group that connect the first compound of formula Ito the second compound of formula I in the dimer. In some embodiments,cleavage of the cleavable linking group may occur in vivo, for instancein the gastrointestinal tract (e.g., stomach, small intestine, largeintestine, etc.), or a desired site of action of the compound. Incertain cases, compounds that include a cleavable linking group mayfacilitate delivery of the pharmaceutically active forms of the compoundat a desired site of action, or after a desired amount of time afteradministration of the dimer (e.g., delayed release formulations,controlled release formulations, and the like).

Formula B

In certain embodiments, the compound is a compound of formula (B):

wherein either Y¹¹ is —C(═O)—O—X¹ and Y¹² is hydrogen, or Y¹² is—C(═O)—O—X¹ and Y¹¹ is hydrogen;

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (B); and

X¹ is a H, C₁₋₆ alkyl or a progroup;

or a salt or stereoisomer thereof.

Formula (IIa) and (IIb)

In certain embodiments of formula (B), the compound is a compound offormula (IIa) or (IIb):

whereinR¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (IIa) or (IIb);andX¹ is hydrogen, C₁₋₆ alkyl or a progroup;or a salt or stereoisomer thereof.

In some embodiments of formula (IIa) and (IIb), the compound is a dimer,where R¹⁵ includes a linking group and a compound of formula (IIa) or(IIb). In certain embodiments, the compound is a symmetrical dimer. Incertain embodiments, the compound is an unsymmetrical dimer. In someinstances, R¹⁵ includes a linking group and a compound of formula (IIa).In some instances, R¹⁵ includes a linking group and a compound offormula (IIb).

In certain embodiments, the compound of formula (Ia) is a compound offormula (IIa):

wherein

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —R¹⁵ whereinR¹⁵ includes a linking group and a compound of formula (IIa); and

X¹ is a H, C₁₋₆ alkyl or a progroup;

or a salt or stereoisomer thereof.

In certain embodiments, the compound of formula (Ib) is a compound offormula (IIb):

wherein

R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —R¹⁵ whereinR¹⁵ includes a linking group and a compound of formula (IIb); and

X¹ is a H, C₁₋₆ alkyl or a progroup;

or a salt or stereoisomer thereof.

In certain embodiments, R¹ is as described above regarding compounds offormulae (Ia) and (Ib). For example, in certain embodiments, R¹ isselected from hydrogen, alkyl, substituted alkyl, alkenyl, substitutedalkenyl, alkynyl, substituted alkynyl, cycloalkyl, substitutedcycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substitutedaryl, heteroaryl, substituted heteroaryl, and —R¹⁵ (e.g., as describedherein).

In certain embodiments, R¹ is hydrogen. In certain embodiments, R¹ isalkyl or substituted alkyl. In certain embodiments, R¹ is alkenyl orsubstituted alkenyl. In certain embodiments, R¹ is alkynyl orsubstituted alkynyl. In certain embodiments, R¹ is cycloalkyl orsubstituted cycloalkyl. In certain embodiments, R¹ is cyclohexyl orsubstituted cyclohexyl. In certain embodiments, R¹ is cyclopentyl orsubstituted cyclopentyl. In certain embodiments, R¹ is cyclobutyl orsubstituted cyclobutyl. In certain embodiments, R¹ is cyclopropyl orsubstituted cyclopropyl. In certain embodiments, R¹ is heterocyclyl orsubstituted heterocyclyl. In certain embodiments, R¹ is4-tetrahydropyranyl or substituted 4-tetrahydropyranyl. In certainembodiments, R¹ is aryl or substituted aryl. In certain embodiments, R¹is phenyl or substituted phenyl. In certain embodiments, R¹ isheteroaryl or substituted heteroaryl. In certain embodiments, R¹ ispyridyl or substituted pyridyl. In certain embodiments, R¹ is a2-pyridyl, a 3-pyridyl or 4-pyridyl. In certain embodiments, R¹ is asubstituted 2-pyridyl, a substituted 3-pyridyl or a substituted4-pyridyl.

In certain embodiments of any of formulae (Ia), (Ib), (IIa) or (IIb), R¹is a substituted alkenyl. In certain embodiments, R¹ is:

wherein X^(1b) is selected from C₁₋₆ alkyl and a progroup.

In certain embodiments, the compound has the formula:

wherein X¹ and X^(1b) are independently hydrogen, C₁₋₆ alkyl or aprogroup; or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein X¹ and X^(1b) are independently hydrogen, C₁₋₆ alkyl or aprogroup; or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein X¹ and X^(1b) are independently hydrogen, C₁₋₆ alkyl or aprogroup; or a salt or stereoisomer thereof.

In certain embodiments, the compound is a symmetrical dimer and X¹ andX^(1b) are the same. In some instances, the compound is an unsymmetricaldimer where X¹ and X^(1b) are different. In some instances, X¹ andX^(1b) are independently a C₁₋₆ alkyl. In some instances, X¹ and X^(1b)are independently an alkyl or a substituted alkyl. In certain instances,the compound has the structure:

In certain embodiments, R is alkyl, such as C₁₋₆ alkyl. In certainembodiments, R¹ is methyl. In certain embodiments, R¹ is ethyl. Incertain embodiments, R¹ is propyl. In certain embodiments, R¹ is butyl.In certain embodiments, R¹ is pentyl. In certain embodiments, R¹ ishexyl. The C₁₋₆ alkyl may be unbranched or branched. For example, R¹ maybe propyl, such as n-propyl or iso-propyl. For example, R¹ may be butyl,such as n-butyl, sec-butyl (1-methylpropyl), iso-butyl (2-methylpropyl)or tert-butyl (1,1-dimethylethyl).

In certain embodiments, R¹ is substituted alkyl, such as substitutedC₁₋₆ alkyl. In certain embodiments, R¹ is substituted methyl. In certainembodiments, R¹ is substituted ethyl. In certain embodiments, R¹ issubstituted propyl. In certain embodiments, R¹ is substituted butyl. Incertain embodiments, R¹ is substituted pentyl. In certain embodiments,R¹ is substituted hexyl. Substituents on R¹ include, but are not limitedto, halogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl,alkynyl, substituted alkynyl, alkoxy, substituted alkoxy, hydroxyl,carboxyl, carboxyl ester, amino, substituted amino, acyl, aminoacyl,acylamino, thioalkoxy, sulfonyl, aminosulfonyl, sulfonylamino,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. For example, R¹ may be a substituted alkyl (e.g.,substituted C₁₋₆ alkyl), substituted by a hydroxyl. In some instances,R¹ is a substituted alkyl (e.g., substituted C₁₋₆ alkyl), substituted byalkoxy or substituted alkoxy, such as a C₁₋₆ alkoxy or a C₁₋₆substituted alkoxy. In some instances, R¹ is a substituted alkyl (e.g.,substituted C₁₋₆ alkyl), substituted by amino or substituted amino. Insome instances, R¹ is a substituted alkyl (e.g., substituted C₁₋₆alkyl), substituted by carboxyl or carboxyl ester. In some instances, R¹is a substituted alkyl (e.g., substituted C₁₋₆ alkyl), substituted byaminoacyl or acylamino (e.g., —CON(R)₂, wherein each R is independentlyhydrogen, a C₁₋₆ alkyl or a substituted C₁₋₆ alkyl). In some instances,R¹ is a substituted alkyl (e.g., substituted C₁₋₆ alkyl), substituted bythioalkoxy or sulfonyl. In some instances, R¹ is a substituted alkyl(e.g., substituted C₁₋₆ alkyl), substituted by cycloalkyl or substitutedcycloalkyl, such as, for example, C₃₋₈ cycloalkyl or C₃₋₈ substitutedcycloalkyl, or C₃₋₆ cycloalkyl or C₃₋₆ substituted cycloalkyl, or C₃₋₅cycloalkyl or C₃₋₅ substituted cycloalkyl, or C₃₋₄ cycloalkyl or C₃₋₄substituted cycloalkyl. In some instances, R¹ is a substituted alkyl(e.g., substituted C₁₋₆ alkyl), substituted by heterocyclyl orsubstituted heterocyclyl, such as, for example, C₃₋₈ heterocyclyl orC₃₋₈ substituted heterocyclyl, or C₃₋₆ heterocyclyl or C₃₋₆ substitutedheterocyclyl, or C₃₋₅ heterocyclyl or C₃₋₅ substituted heterocyclyl, orC₃₋₄ heterocyclyl or C₃₋₄ substituted heterocyclyl. In some instances,R¹ is a substituted alkyl (e.g., substituted C₁₋₆ alkyl), substituted byaryl or substituted aryl, such as, for example, C₃₋₆ aryl or C₃₋₆substituted aryl, such as phenyl or substituted phenyl. In someinstances, R¹ is a substituted alkyl (e.g., substituted C₁₋₆ alkyl),substituted by heteroaryl or substituted heteroaryl, such as, forexample, C₃₋₆ heteroaryl or C₃₋₆ substituted heteroaryl. Combinations ofthe above substituents on R¹ are also included.

For example, in certain embodiments, R¹ is alkyl, substituted alkyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, such that the compound of formula (IIa) has a structureselected from the following:

wherein

X¹ is as described below;

n is 0, 1, 2, 3, 4 or 5; and

each R is independently selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, sulfoxy and phosphate,

or a salt or stereoisomer thereof.

In certain embodiments, R¹ is alkyl, substituted alkyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, or substituted heteroaryl, such that thecompound of formula (IIb) has a structure selected from the following:

wherein

X¹ is as described below;

n is 0, 1, 2, 3, 4 or 5; and

each R is independently selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, sulfoxy and phosphate,

or a salt or stereoisomer thereof.

In certain embodiments, each R is independently selected from hydrogen,alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, cycloalkyl, substituted cycloalkyl, heterocyclyl,substituted heterocyclyl, aryl, substituted aryl, heteroaryl, andsubstituted heteroaryl. In certain embodiments, R is hydrogen. Incertain embodiments, R is alkyl or substituted alkyl, such as C₁₋₆ alkyl(e.g., methyl, ethyl, propyl, butyl, pentyl, or hexyl) or C₁₋₆substituted alkyl. In certain embodiments, R is alkenyl or substitutedalkenyl. In certain embodiments, R is alkynyl or substituted alkynyl. Incertain embodiments, R is cycloalkyl or substituted cycloalkyl, such asC₃₋₈ cycloalkyl or C₃₋₈ substituted cycloalkyl, or C₃₋₆ cycloalkyl orC₃₋₆ substituted cycloalkyl, or C₃₋₅ cycloalkyl or C₃₋₅ substitutedcycloalkyl. In certain embodiments, R is heterocyclyl or substitutedheterocyclyl, such as C₃₋₈ heterocyclyl or C₃₋₈ substitutedheterocyclyl, or C₃₋₆ heterocyclyl or C₃₋₆ substituted heterocyclyl, orC₃₋₅ heterocyclyl or C₃₋₅ substituted heterocyclyl. In certainembodiments, R is aryl or substituted aryl, such as C₃₋₈ aryl or C₃₋₈substituted aryl, or C₃₋₆ aryl or C₃₋₆ substituted aryl (e.g., phenyl orsubstituted phenyl). In certain embodiments, R is heteroaryl orsubstituted heteroaryl, such as C₃₋₈ heteroaryl or C₃₋₈ substitutedheteroaryl, or C₃₋₆ heteroaryl or C₃₋₆ substituted heteroaryl. Inparticular embodiments, R is —P(O)(OH)₂ or a salt thereof, and in otherembodiments, R is —S(O)₂OH or a salt thereof.

In certain embodiments, X¹ is H, C₁₋₆ alkyl or a progroup. In certainembodiments, X¹ is H. In certain embodiments, X¹ is C₁₋₆ alkyl. Incertain embodiments, X¹ is methyl. In certain embodiments, X¹ is ethyl.In certain embodiments, X¹ is propyl. In certain embodiments, X¹ isbutyl. In certain embodiments, X¹ is pentyl. In certain embodiments, X¹is hexyl. The C₁₋₆ alkyl may be unbranched or branched. For example, X¹may be propyl, such as n-propyl or iso-propyl. For example, X¹ may bebutyl, such as n-butyl, sec-butyl (1-methylpropyl), iso-butyl(2-methylpropyl) or tert-butyl (1,1-dimethylethyl).

In certain embodiments, X¹ is a progroup.

In certain embodiments, X¹ is a progroup of the formula:

wherein

L¹ is a linking group;

X² is optional and selected from O, N and S;

R² is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, acyl, aminoacyl,carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl; and

R³ and R⁴ are each independently optional and selected from hydrogen,alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, oxo, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl; or

R² together with X² and either R³ or R⁴ form a heterocyclyl, substitutedheterocyclyl, heteroaryl or substituted heteroaryl.

In certain embodiments, L¹ is a linking group. By “linking group” ismeant a moiety that connects two or more portions of a compound togetherthrough one or more covalent bonds. For example, the linking group L¹may connect X² to the rest of the compound, such as for example, thecarboxyl oxygen of the compound of formula II.

In certain embodiments, L¹ is C₁₋₆ alkyl or substituted C₁₋₆ alkyl. Incertain embodiments, L¹ is C₁₋₆ alkyl. In certain embodiments, L¹ ismethyl. In certain embodiments, L¹ is ethyl. In certain embodiments, L¹is propyl. In certain embodiments, L¹ is butyl. In certain embodiments,L¹ is pentyl. In certain embodiments, L¹ is hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl. In certain embodiments, L¹ issubstituted methyl. In certain embodiments, L¹ is substituted ethyl. Incertain embodiments, L¹ is substituted propyl. In certain embodiments,L¹ is substituted butyl. In certain embodiments, L¹ is substitutedpentyl. In certain embodiments, L¹ is substituted hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with one or more groups selected from alkyl (e.g., C₁₋₆alkyl), substituted alkyl (e.g., substituted C₁₋₆ alkyl), alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, and substituted heteroaryl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with a C₁₋₆ alkyl. In certain embodiments, L¹ is methylsubstituted with one or two methyl groups. In certain embodiments, L¹ isethyl substituted with one or two methyl groups.

In certain embodiments, X² is optional and selected from O, N and S. Incertain embodiments, X² is not present. In embodiments where X² is notpresent, L¹ may be directly connected to R². In embodiments where X² isnot present, L¹ may be directly connected to R³, if present. Inembodiments where X² is not present, L¹ may be directly connected to R⁴,if present. In certain embodiments, X² is present. In embodiments whereX² is present, X² may be O, N or S. In certain embodiments, X² is O. Insome embodiments, when X² is, then R³ and R⁴ are not present. In certainembodiments, X² is N. In some embodiments, when X² is N, then R³ ispresent and R⁴ is not present. In certain embodiments, X² is S. In someembodiments, when X² is S, then R³ and R⁴ are present.

In certain embodiments, R² is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, acyl,aminoacyl, carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl. In certain embodiments, R² ishydrogen. In certain embodiments, R² is alkyl or substituted alkyl. Incertain embodiments, R² is alkenyl or substituted alkenyl. In certainembodiments, R² is alkynyl or substituted alkynyl. In certainembodiments, R² is acyl. In certain embodiments, R² is aminoacyl. Incertain embodiments, R² is carboxyl or carboxyl ester. In certainembodiments, R² is cycloalkyl or substituted cycloalkyl. In certainembodiments, R² is heterocyclyl or substituted heterocyclyl. In certainembodiments, R² is aryl or substituted aryl. In certain embodiments, R²is heteroaryl or substituted heteroaryl.

In certain embodiments, R³ and R⁴ are each independently optional andselected from hydrogen, alkyl, substituted alkyl, alkenyl, substitutedalkenyl, alkynyl, substituted alkynyl, oxo, cycloalkyl, substitutedcycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substitutedaryl, heteroaryl, and substituted heteroaryl.

In certain embodiments, R³ is not present. In certain embodiments, R³ ispresent and is selected from hydrogen, alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, oxo,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R³ is hydrogen. In certainembodiments, R³ is alkyl or substituted alkyl. In certain embodiments,R³ is alkenyl or substituted alkenyl. In certain embodiments, R³ isalkynyl or substituted alkynyl. In certain embodiments, R³ is oxo. Incertain embodiments, R³ is cycloalkyl or substituted cycloalkyl. Incertain embodiments, R³ is heterocyclyl or substituted heterocyclyl. Incertain embodiments, R³ is aryl or substituted aryl. In certainembodiments, R³ is heteroaryl or substituted heteroaryl.

In certain embodiments, R⁴ is not present. In certain embodiments, R⁴ ispresent and is selected from hydrogen, alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, oxo,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R⁴ is hydrogen. In certainembodiments, R⁴ is alkyl or substituted alkyl. In certain embodiments,R⁴ is alkenyl or substituted alkenyl. In certain embodiments, R⁴ isalkynyl or substituted alkynyl. In certain embodiments, R⁴ is oxo. Incertain embodiments, R⁴ is cycloalkyl or substituted cycloalkyl. Incertain embodiments, R⁴ is heterocyclyl or substituted heterocyclyl. Incertain embodiments, R⁴ is aryl or substituted aryl. In certainembodiments, R⁴ is heteroaryl or substituted heteroaryl.

In certain embodiments, X² is N. In certain embodiments, when X² is N,then R³ is present and R⁴ is not present. In certain embodiments, X² isS. In some embodiments, when X² is S, then R³ and R⁴ are present. Incertain embodiments, when X² is S, then R³ and R⁴ are both oxo.

In certain embodiments, R² together with X² and either R³ or R⁴ form aheterocyclyl, substituted heterocyclyl, heteroaryl or substitutedheteroaryl. In certain embodiments, R² together with X² and either R³ orR⁴ form a heterocyclyl. In certain embodiments, R² together with X² andeither R³ or R⁴ form a substituted heterocyclyl. In certain embodiments,R² together with X² and either R³ or R⁴ form a heteroaryl. In certainembodiments, R² together with X² and either R³ or R⁴ form a substitutedheteroaryl. In certain embodiments, X² is N. In certain embodiments,when X² is N, then R³ is present and R⁴ is not present. As such, incertain embodiments, R² and R³ together with the N to which they areattached form a heterocyclyl. In certain embodiments, R² and R³ togetherwith the N to which they are attached form a substituted heterocyclyl.In certain embodiments, R² and R³ together with the N to which they areattached form a heteroaryl. In certain embodiments, R² and R³ togetherwith the N to which they are attached form a substituted heteroaryl. Forexample, in certain embodiments, R² and R³ together with the N to whichthey are attached form a ring selected from piperazinyl,1,3-oxazolidinyl, pyrrolidinyl, morpholinyl, imidazolidinyl,pyrazolidinyl, isoxazolidinyl, triazolidinyl, and piperidinyl.

In certain embodiments, X¹ is a progroup selected from:

wherein

L¹ is a C₁₋₆ alkyl or substituted C₁₋₆ alkyl;

R⁵ and R⁶ are each independently selected from hydrogen, alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl; or

R⁵ and R⁶ together with the nitrogen to which they are attached form aheterocyclyl, substituted heterocyclyl, heteroaryl or substitutedheteroaryl;

R², R³ and R⁴ are as described above; and

R⁷ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —OR¹⁴ whereR¹⁴ is selected from alkyl, substituted alkyl, alkenyl, substitutedalkenyl, alkynyl, substituted alkynyl, cycloalkyl, substitutedcycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substitutedaryl, heteroaryl, and substituted heteroaryl.

As described above, in certain embodiments, X¹ is a progroup of theformula:

In certain embodiments, X² is not present, R² is aminoacyl, R³ is notpresent, and R⁴ is not present. As such, in certain embodiments, X¹ hasthe formula:

In certain embodiments, L¹ is C₁₋₆ alkyl or substituted C₁₋₆ alkyl. Incertain embodiments, L¹ is C₁₋₆ alkyl. In certain embodiments, L¹ ismethyl. In certain embodiments, L¹ is ethyl. In certain embodiments, L¹is propyl. In certain embodiments, L¹ is butyl. In certain embodiments,L¹ is pentyl. In certain embodiments, L¹ is hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl. In certain embodiments, L¹ issubstituted methyl. In certain embodiments, L¹ is substituted ethyl. Incertain embodiments, L¹ is substituted propyl. In certain embodiments,L¹ is substituted butyl. In certain embodiments, L¹ is substitutedpentyl. In certain embodiments, L¹ is substituted hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with one or more groups selected from alkyl (e.g., C₁₋₆alkyl), substituted alkyl (e.g., substituted C₁₋₆ alkyl), alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, and substituted heteroaryl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with a C₁₋₆ alkyl. In certain embodiments, L¹ is methylsubstituted with one or two methyl groups. In certain embodiments, L¹ isethyl substituted with one or two methyl groups.

In certain embodiments, R⁵ and R⁶ are each independently selected fromhydrogen, alkyl, substituted alkyl, alkenyl, substituted alkenyl,alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl.

In certain embodiments, R⁵ is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R⁵ is hydrogen. In certainembodiments, R⁵ is alkyl or substituted alkyl. In certain embodiments,R⁵ is alkenyl or substituted alkenyl. In certain embodiments, R⁵ isalkynyl or substituted alkynyl. In certain embodiments, R⁵ is cycloalkylor substituted cycloalkyl. In certain embodiments, R⁵ is heterocyclyl orsubstituted heterocyclyl. In certain embodiments, R⁵ is aryl orsubstituted aryl. In certain embodiments, R⁵ is heteroaryl orsubstituted heteroaryl.

In certain embodiments, R⁶ is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R⁶ is hydrogen. In certainembodiments, R⁶ is alkyl or substituted alkyl. In certain embodiments,R⁶ is alkenyl or substituted alkenyl. In certain embodiments, R⁶ isalkynyl or substituted alkynyl. In certain embodiments, R⁶ is cycloalkylor substituted cycloalkyl. In certain embodiments, R⁶ is heterocyclyl orsubstituted heterocyclyl. In certain embodiments, R⁶ is aryl orsubstituted aryl. In certain embodiments, R⁶ is heteroaryl orsubstituted heteroaryl.

In certain embodiments, R⁵ and R⁶ are each independently selected fromhydrogen, alkyl (e.g., C₁₋₆ alkyl), and substituted alkyl (e.g.,substituted C₁₋₆ alkyl). In certain embodiments, R⁵ is hydrogen and R⁶is hydrogen. In certain embodiments, R⁵ is hydrogen and R⁶ is alkyl,such as C₁₋₆ alkyl (e.g., methyl, ethyl, propyl, butyl, pentyl orhexyl). In certain embodiments, R⁵ is alkyl such as C₁₋₆ alkyl, and R⁶is alkyl such as C₁₋₆ alkyl. For example, in some instances, R⁵ ismethyl and R⁶ is methyl, or one of R⁵ and R⁶ is methyl and the other isethyl, or R⁵ is ethyl and R⁶ is ethyl. In certain embodiments, R⁵ ishydrogen and R⁶ is substituted alkyl, such as substituted C₁₋₆ alkyl(e.g., methyl, ethyl, propyl, butyl, pentyl or hexyl). In certainembodiments, R⁵ is substituted alkyl such as substituted C₁₋₆ alkyl, andR⁶ is substituted alkyl such as substituted C₁₋₆ alkyl.

In certain embodiments, R⁵ is substituted C₁₋₆ alkyl, where the C₁₋₆alkyl is substituted with one or more groups selected from alkyl,substituted alkyl, alkoxy, substituted alkoxy, oxo, acyl, acyloxy,carboxyl, carboxyl ester, amine, substituted amine, aminoacyl,acylamino, cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. For example, in certain embodiments, R⁵ is substituted C₁₋₆alkyl, such as, but not limited to, benzyl, 2-methoxyethyl,carboxymethyl, carboxypropyl, 2-(methylethoxy)ethyl, 2-ethoxyethyl,(tert-butyloxycarbonyl)methyl, (ethoxycarbonyl)methyl,(methylethyl)oxycarbonylmethyl, or ethoxycarbonylmethyl.

In certain embodiments, R⁶ is substituted C₁₋₆ alkyl, where the C₁₋₆alkyl is substituted with one or more groups selected from alkyl,substituted alkyl, alkoxy, substituted alkoxy, oxo, acyl, acyloxy,carboxyl, carboxyl ester, amine, substituted amine, aminoacyl,acylamino, cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. For example, in certain embodiments, R⁶ is substituted C₁₋₆alkyl, such as, but not limited to, benzyl, 2-methoxyethyl,carboxymethyl, carboxypropyl, 2-(methylethoxy)ethyl, 2-ethoxyethyl,(tert-butyloxycarbonyl)methyl, (ethoxycarbonyl)methyl,(methylethyl)oxycarbonylmethyl, or ethoxycarbonylmethyl.

In certain embodiments, R⁵ and R⁶ together with the nitrogen to whichthey are attached form a heterocyclyl, substituted heterocyclyl,heteroaryl or substituted heteroaryl. In certain embodiments, R⁵ and R⁶together with the nitrogen to which they are attached form aheterocyclyl. In certain embodiments, R⁵ and R⁶ together with thenitrogen to which they are attached form a substituted heterocyclyl. Incertain embodiments, R⁵ and R⁶ together with the nitrogen to which theyare attached form a heteroaryl. In certain embodiments, R⁵ and R⁶together with the nitrogen to which they are attached form a substitutedheteroaryl. In certain embodiments, R⁵ and R⁶ together with the nitrogento which they are attached form a ring selected from piperazinyl,1,3-oxazolidinyl, 2-oxo(1,3-oxazolidinyl), pyrrolidinyl, morpholinyl,imidazolidinyl, pyrazolidinyl, isoxazolidinyl, triazolidinyl, andpiperidinyl.

As described above, in certain embodiments, X¹ is a progroup of theformula:

In certain embodiments, X² is O, R² is acyl, R³ is not present, and R⁴is not present. As such, in certain embodiments, X¹ has the formula:

In certain embodiments, L¹ is C₁₋₆ alkyl or substituted C₁₋₆ alkyl. Incertain embodiments, L¹ is C₁₋₆ alkyl. In certain embodiments, L¹ ismethyl. In certain embodiments, L¹ is ethyl. In certain embodiments, L¹is propyl. In certain embodiments, L¹ is butyl. In certain embodiments,L¹ is pentyl. In certain embodiments, L¹ is hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl. In certain embodiments, L¹ issubstituted methyl. In certain embodiments, L¹ is substituted ethyl. Incertain embodiments, L¹ is substituted propyl. In certain embodiments,L¹ is substituted butyl. In certain embodiments, L¹ is substitutedpentyl. In certain embodiments, L¹ is substituted hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with one or more groups selected from alkyl (e.g., C₁₋₆alkyl), substituted alkyl (e.g., substituted C₁₋₆ alkyl), alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, and substituted heteroaryl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with a C₁₋₆ alkyl. In certain embodiments, L¹ is methylsubstituted with one or two methyl groups. In certain embodiments, L¹ isethyl substituted with one or two methyl groups.

In certain embodiments, R⁷ is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, and —OR¹⁴ where R¹⁴ is selected from alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R⁷ is hydrogen. In certainembodiments, R⁷ is alkyl or substituted alkyl. In certain embodiments,R⁷ is alkenyl or substituted alkenyl. In certain embodiments, R⁷ isalkynyl or substituted alkynyl. In certain embodiments, R⁷ is cycloalkylor substituted cycloalkyl. In certain embodiments, R⁷ is heterocyclyl orsubstituted heterocyclyl. In certain embodiments, R⁷ is aryl orsubstituted aryl. In certain embodiments, R⁷ is heteroaryl orsubstituted heteroaryl. In certain embodiments, R⁷ is —OR¹⁴ where R¹⁴ isselected from alkyl, substituted alkyl, alkenyl, substituted alkenyl,alkynyl, substituted alkynyl, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl. In certain embodiments, R¹⁴ isalkyl or substituted alkyl. In certain embodiments, R¹⁴ is alkenyl orsubstituted alkenyl. In certain embodiments, R¹⁴ is alkynyl orsubstituted alkynyl. In certain embodiments, R¹⁴ is cycloalkyl orsubstituted cycloalkyl. In certain embodiments, R¹⁴ is heterocyclyl orsubstituted heterocyclyl. In certain embodiments, R¹⁴ is aryl orsubstituted aryl. In certain embodiments, R¹⁴ is heteroaryl orsubstituted heteroaryl.

In certain embodiments, R⁷ is alkyl or substituted alkyl, such as C₁₋₆alkyl or substituted C₁₋₆ alkyl. In certain embodiments, R⁷ is C₁₋₆alkyl, such as C₁₋₄ alkyl. For example, R₇ may be selected from methyl,ethyl, propyl (e.g., n-propyl or iso-propyl), and butyl (e.g., n-butyl,sec-butyl (1-methylpropyl), iso-butyl (2-methylpropyl) or tert-butyl(1,1-dimethylethyl)).

In certain embodiments, R⁷ is substituted alkyl, such as substitutedC₁₋₆ alkyl. In certain embodiments, R⁷ is substituted C₁₋₆ alkyl, wherethe alkyl is substituted with one or more groups selected from alkyl,substituted alkyl, alkoxy, substituted alkoxy, oxo, acyl, acyloxy,carboxyl, carboxyl ester, amine, substituted amine, aminoacyl,acylamino, cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl.

For example, in certain embodiments, R⁷ is selected from ethoxy,methylethoxy, iso-propyl, phenyl, cyclohexyl, cyclohexyloxy,—CH(NH₂)CH₂COOH, —CH₂CH(NH₂)COOH, —CH(NHC(O)CH₂NH₂)CH₂COOH, and—CH₂CH(NHC(O)CH₂NH₂)COOH.

As described above, in certain embodiments, X¹ is a progroup of theformula:

In certain embodiments, X² is N, R² is present, R³ is present, and R⁴ isnot present. As such, in certain embodiments, X¹ has the formula:

In certain embodiments, L¹ is C₁₋₆ alkyl or substituted C₁₋₆ alkyl. Incertain embodiments, L¹ is C₁₋₆ alkyl. In certain embodiments, L¹ ismethyl. In certain embodiments, L¹ is ethyl. In certain embodiments, L¹is propyl. In certain embodiments, L¹ is butyl. In certain embodiments,L¹ is pentyl. In certain embodiments, L¹ is hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl. In certain embodiments, L¹ issubstituted methyl. In certain embodiments, L¹ is substituted ethyl. Incertain embodiments, L¹ is substituted propyl. In certain embodiments,L¹ is substituted butyl. In certain embodiments, L¹ is substitutedpentyl. In certain embodiments, L¹ is substituted hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with one or more groups selected from alkyl (e.g., C₁₋₆alkyl), substituted alkyl (e.g., substituted C₁₋₆ alkyl), alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, and substituted heteroaryl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with a C₁₋₆ alkyl. In certain embodiments, L¹ is methylsubstituted with one or two methyl groups. In certain embodiments, L¹ isethyl substituted with one or two methyl groups.

In certain embodiments, R² is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, acyl,aminoacyl, carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl. In certain embodiments, R² ishydrogen. In certain embodiments, R² is alkyl or substituted alkyl. Incertain embodiments, R² is alkenyl or substituted alkenyl. In certainembodiments, R² is alkynyl or substituted alkynyl. In certainembodiments, R² is acyl. In certain embodiments, R² is aminoacyl. Incertain embodiments, R² is carboxyl or carboxyl ester. In certainembodiments, R² is cycloalkyl or substituted cycloalkyl. In certainembodiments, R² is heterocyclyl or substituted heterocyclyl. In certainembodiments, R² is aryl or substituted aryl. In certain embodiments, R²is heteroaryl or substituted heteroaryl.

For example, in some embodiments, R² is C₁₋₆ alkyl, such as methyl,ethyl, propyl, butyl, pentyl or hexyl. In some embodiments, R² iscarboxyl or carboxyl ester, such as —COOR^(a), where R^(a) is hydrogenor C₁₋₆ alkyl. In some embodiments, R² is aryl or substituted aryl, suchas phenyl or substituted phenyl.

In certain embodiments, R³ is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, oxo,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R³ is hydrogen. In certainembodiments, R³ is alkyl or substituted alkyl. In certain embodiments,R³ is alkenyl or substituted alkenyl. In certain embodiments, R³ isalkynyl or substituted alkynyl. In certain embodiments, R³ is oxo. Incertain embodiments, R³ is cycloalkyl or substituted cycloalkyl. Incertain embodiments, R³ is heterocyclyl or substituted heterocyclyl. Incertain embodiments, R³ is aryl or substituted aryl. In certainembodiments, R³ is heteroaryl or substituted heteroaryl.

For example, in some embodiments, R³ is C₁₋₆ alkyl, such as methyl,ethyl, propyl, butyl, pentyl or hexyl. In some embodiments, R³ issubstituted C₁₋₆ alkyl, such as substituted C₁₋₃ alkyl or substitutedC₁₋₂ alkyl.

In certain embodiments, R² and R³ together with the N to which they areattached form a heterocyclyl. In certain embodiments, R² and R³ togetherwith the N to which they are attached form a substituted heterocyclyl.In certain embodiments, R² and R³ together with the N to which they areattached form a succinimidyl. In certain embodiments, R² and R³ togetherwith the N to which they are attached form a heteroaryl. In certainembodiments, R² and R³ together with the N to which they are attachedform a substituted heteroaryl. For example, in certain embodiments, R²and R³ together with the N to which they are attached form a ringselected from piperazinyl, 1,3-oxazolidinyl, pyrrolidinyl, morpholinyl,imidazolidinyl, pyrazolidinyl, isoxazolidinyl, triazolidinyl, andpiperidinyl.

As described above, in certain embodiments, X¹ is a progroup of theformula:

In certain embodiments, X² is S, R² is present, R³ is oxo, and R⁴ isoxo. As such, in certain embodiments, X¹ has the formula:

In certain embodiments, L¹ is C₁₋₆ alkyl or substituted C₁₋₆ alkyl. Incertain embodiments, L¹ is C₁₋₆ alkyl. In certain embodiments, L¹ ismethyl. In certain embodiments, L¹ is ethyl. In certain embodiments, L¹is propyl. In certain embodiments, L¹ is butyl. In certain embodiments,L¹ is pentyl. In certain embodiments, L¹ is hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl. In certain embodiments, L¹ issubstituted methyl. In certain embodiments, L¹ is substituted ethyl. Incertain embodiments, L¹ is substituted propyl. In certain embodiments,L¹ is substituted butyl. In certain embodiments, L¹ is substitutedpentyl. In certain embodiments, L¹ is substituted hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with one or more groups selected from alkyl (e.g., C₁₋₆alkyl), substituted alkyl (e.g., substituted C₁₋₆ alkyl), alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, and substituted heteroaryl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with a C₁₋₆ alkyl. In certain embodiments, L¹ is methylsubstituted with one or two methyl groups. In certain embodiments, L¹ isethyl substituted with one or two methyl groups.

In certain embodiments, R² is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, acyl,aminoacyl, carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl. In certain embodiments, R² ishydrogen. In certain embodiments, R² is alkyl or substituted alkyl. Incertain embodiments, R² is alkenyl or substituted alkenyl. In certainembodiments, R² is alkynyl or substituted alkynyl. In certainembodiments, R² is acyl. In certain embodiments, R² is aminoacyl. Incertain embodiments, R² is carboxyl or carboxyl ester. In certainembodiments, R² is cycloalkyl or substituted cycloalkyl. In certainembodiments, R² is heterocyclyl or substituted heterocyclyl. In certainembodiments, R² is aryl or substituted aryl. In certain embodiments, R²is heteroaryl or substituted heteroaryl.

For example, in some embodiments, R² is C₁₋₆ alkyl, such as methyl,ethyl, propyl, butyl, pentyl or hexyl.

As described above, in certain embodiments, X¹ is a progroup of theformula:

In certain embodiments, X² is N, R² is present, R³ is present, and R⁴ ispresent. In these embodiments, the N is a quaternary amine. As such, incertain embodiments, X¹ has the formula:

In certain embodiments, L¹ is C₁₋₆ alkyl or substituted C₁₋₆ alkyl. Incertain embodiments, L¹ is C₁₋₆ alkyl. In certain embodiments, L¹ ismethyl. In certain embodiments, L¹ is ethyl. In certain embodiments, L¹is propyl. In certain embodiments, L¹ is butyl. In certain embodiments,L¹ is pentyl. In certain embodiments, L¹ is hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl. In certain embodiments, L¹ issubstituted methyl. In certain embodiments, L¹ is substituted ethyl. Incertain embodiments, L¹ is substituted propyl. In certain embodiments,L¹ is substituted butyl. In certain embodiments, L¹ is substitutedpentyl. In certain embodiments, L¹ is substituted hexyl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with one or more groups selected from alkyl (e.g., C₁₋₆alkyl), substituted alkyl (e.g., substituted C₁₋₆ alkyl), alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, and substituted heteroaryl. In certainembodiments, L¹ is substituted C₁₋₆ alkyl, where the alkyl issubstituted with a C₁₋₆ alkyl. In certain embodiments, L¹ is methylsubstituted with one or two methyl groups. In certain embodiments, L¹ isethyl substituted with one or two methyl groups.

In certain embodiments, R² is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, acyl,aminoacyl, carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl. In certain embodiments, R² ishydrogen. In certain embodiments, R² is alkyl or substituted alkyl. Incertain embodiments, R² is alkenyl or substituted alkenyl. In certainembodiments, R² is alkynyl or substituted alkynyl. In certainembodiments, R² is acyl. In certain embodiments, R² is aminoacyl. Incertain embodiments, R² is carboxyl or carboxyl ester. In certainembodiments, R² is cycloalkyl or substituted cycloalkyl. In certainembodiments, R² is heterocyclyl or substituted heterocyclyl. In certainembodiments, R² is aryl or substituted aryl. In certain embodiments, R²is heteroaryl or substituted heteroaryl.

For example, in some embodiments, R² is C₁₋₆ alkyl, such as methyl,ethyl, propyl, butyl, pentyl or hexyl. In some embodiments, R² iscarboxyl or carboxyl ester, such as —COOR^(a), where R^(a) is hydrogenor C₁₋₆ alkyl. In some embodiments, R² is aryl or substituted aryl, suchas phenyl or substituted phenyl.

In certain embodiments, R³ is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, oxo,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R³ is hydrogen. In certainembodiments, R³ is alkyl or substituted alkyl. In certain embodiments,R³ is alkenyl or substituted alkenyl. In certain embodiments, R³ isalkynyl or substituted alkynyl. In certain embodiments, R³ is oxo. Incertain embodiments, R³ is cycloalkyl or substituted cycloalkyl. Incertain embodiments, R³ is heterocyclyl or substituted heterocyclyl. Incertain embodiments, R³ is aryl or substituted aryl. In certainembodiments, R³ is heteroaryl or substituted heteroaryl.

For example, in some embodiments, R³ is C₁₋₆ alkyl, such as methyl,ethyl, propyl, butyl, pentyl or hexyl. In some embodiments, R³ issubstituted C₁₋₆ alkyl, such as substituted C₁₋₃ alkyl or substitutedC₁₋₂ alkyl.

In certain embodiments, R⁴ is selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, oxo,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl. In certain embodiments, R⁴ is hydrogen. In certainembodiments, R⁴ is alkyl or substituted alkyl. In certain embodiments,R⁴ is alkenyl or substituted alkenyl. In certain embodiments, R⁴ isalkynyl or substituted alkynyl. In certain embodiments, R⁴ is oxo. Incertain embodiments, R⁴ is cycloalkyl or substituted cycloalkyl. Incertain embodiments, R⁴ is heterocyclyl or substituted heterocyclyl. Incertain embodiments, R⁴ is aryl or substituted aryl. In certainembodiments, R⁴ is heteroaryl or substituted heteroaryl.

For example, in some embodiments, R⁴ is C₁₋₆ alkyl, such as methyl,ethyl, propyl, butyl, pentyl or hexyl. In some embodiments, R⁴ issubstituted C₁₋₆ alkyl, such as substituted C₁₋₃ alkyl or substitutedC₁₋₂ alkyl.

In certain embodiments, R² and R³ together with the N to which they areattached form a heterocyclyl. In certain embodiments, R² and R³ togetherwith the N to which they are attached form a substituted heterocyclyl.In certain embodiments, R² and R³ together with the N to which they areattached form a heteroaryl. In certain embodiments, R² and R³ togetherwith the N to which they are attached form a substituted heteroaryl. Forexample, in certain embodiments, R² and R³ together with the N to whichthey are attached form a ring selected from piperazinyl,1,3-oxazolidinyl, pyrrolidinyl, morpholinyl, imidazolidinyl,pyrazolidinyl, isoxazolidinyl, triazolidinyl, and piperidinyl.

In certain embodiments, X¹ is a progroup selected from:

wherein R², R³, R⁵, R⁶ and R⁷ are as described above; and R⁸, R⁹, R¹⁰,R¹¹, R¹² and R¹³ are each independently selected from hydrogen, alkyland substituted alkyl.

In the formulae above for X¹, the substituents R², R³, R⁴, R⁵, R⁶, andR⁷ are as described above.

In certain embodiments, X¹ has the formula:

wherein R⁵ and R⁶ are as described above; and R⁸ and R⁹ are eachindependently selected from hydrogen, alkyl and substituted alkyl.

In the formula above for X¹, the substituents R⁵ and R⁶ are as describedabove.

In certain embodiments, R⁸ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R⁸ is hydrogen. In certainembodiments, R⁸ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R⁸ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R⁹ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R⁹ is hydrogen. In certainembodiments, R⁹ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R⁹ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R⁸ and R⁹ are each hydrogen. In certainembodiments, one of R⁸ and R⁹ is hydrogen and the other is alkyl, suchas C₁₋₆ alkyl as described above.

In certain embodiments, X¹ has the formula:

wherein R⁷ is as described above; and R⁸ and R⁹ are each independentlyselected from hydrogen, alkyl and substituted alkyl.

In the formula above for X¹, the substituent R⁷ is as described above.

In certain embodiments, R is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R⁸ is hydrogen. In certainembodiments, R⁸ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R⁸ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R⁹ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R⁹ is hydrogen. In certainembodiments, R⁹ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R⁹ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R⁸ and R⁹ are each hydrogen. In certainembodiments, one of R⁸ and R⁹ is hydrogen and the other is alkyl, suchas C₁₋₆ alkyl as described above.

In certain embodiments, X¹ has the formula:

wherein R² and R are as described above; and R¹⁰, R¹¹, R¹² and R¹³ areeach independently selected from hydrogen, alkyl and substituted alkyl.

In the formula above for X¹, the substituent R² and R³ are as describedabove.

In certain embodiments, R¹⁰ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹⁰ is hydrogen. In certainembodiments, R¹⁰ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹⁰ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹¹ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹¹ is hydrogen. In certainembodiments, R¹¹ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹¹ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹² is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹² is hydrogen. In certainembodiments, R¹² is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹² issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹³ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹³ is hydrogen. In certainembodiments, R¹³ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹³ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹⁰, R¹¹, R¹² and R¹³ are each independentlyselected from hydrogen and C₁₋₆ alkyl. In certain embodiments, R¹⁰, R¹¹,R¹² and R¹³ are each hydrogen. In certain embodiments, one of R¹⁰, R¹¹,R¹² and R¹³ is C₁₋₆ alkyl and the remaining are hydrogen. For example,in some instances, one of R¹⁰, R¹¹, R¹² and R¹³ is methyl and theremaining are hydrogen. In some instances, R¹⁰ is C₁₋₆ alkyl (e.g.,methyl) and R¹¹, R¹² and R¹³ are hydrogen. In some instances, R¹¹ isC₁₋₆ alkyl (e.g., methyl) and R¹⁰, R¹² and R¹³ are hydrogen. In someinstances, R¹² is C₁₋₆ alkyl (e.g., methyl) and R¹⁰, R¹¹ and R¹³ arehydrogen. In some instances, R¹³ is C₁₋₆ alkyl (e.g., methyl) and R¹⁰,R¹¹ and R¹² are hydrogen. In certain embodiments, two of R¹⁰, R¹¹, R¹²and R¹³ are methyl and the remaining are hydrogen. For example, in someinstances, two of R¹⁰, R¹¹, R¹² and R¹³ are methyl and the remaining arehydrogen. In some instances, R¹⁰ and R¹¹ are C₁₋₆ alkyl (e.g., methyl)and R¹² and R¹³ are hydrogen. In some instances, R¹⁰ and R¹² are C₁₋₆alkyl (e.g., methyl) and R¹¹ and R¹³ are hydrogen. In some instances,R¹⁰ and R¹³ are C₁₋₆ alkyl (e.g., methyl) and R¹¹ and R¹² are hydrogen.In some instances, R¹¹ and R¹² are C₁₋₆ alkyl (e.g., methyl) and R andR¹³ are hydrogen. In some instances, R¹¹ and R¹³ are C₁₋₆ alkyl (e.g.,methyl) and R¹⁰ and R¹² are hydrogen. In some instances, R¹² and R¹³ areC₁₋₆ alkyl (e.g., methyl) and R¹⁰ and R¹ are hydrogen.

In certain embodiments, X¹ has the formula:

wherein R² is as described above; and R¹⁰, R¹¹, R¹² and R¹³ are eachindependently selected from hydrogen, alkyl and substituted alkyl.

In the formula above for X¹, the substituent R² is as described above.

In certain embodiments, R¹⁰ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹⁰ is hydrogen. In certainembodiments, R¹⁰ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹⁰ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹¹ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹¹ is hydrogen. In certainembodiments, R¹¹ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹¹ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹² is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹² is hydrogen. In certainembodiments, R¹² is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹² issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹³ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹³ is hydrogen. In certainembodiments, R¹³ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹³ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹⁰, R¹¹, R¹² and R¹³ are each independentlyselected from hydrogen and C₁₋₆ alkyl. In certain embodiments, R¹⁰, R¹¹,R¹² and R¹³ are each hydrogen. In certain embodiments, one of R¹⁰, R¹¹,R¹² and R¹³ is C₁₋₆ alkyl and the remaining are hydrogen. For example,in some instances, one of R¹⁰, R¹¹, R¹² and R¹³ is methyl and theremaining are hydrogen. In some instances, R¹⁰ is C₁₋₆ alkyl (e.g.,methyl) and R¹¹, R¹² and R¹³ are hydrogen. In some instances, R¹¹ isC₁₋₆ alkyl (e.g., methyl) and R¹⁰, R¹² and R¹³ are hydrogen. In someinstances, R¹² is C₁₋₆ alkyl (e.g., methyl) and R¹⁰, R¹¹ and R¹³ arehydrogen. In some instances, R¹³ is C₁₋₆ alkyl (e.g., methyl) and R¹⁰,R¹¹ and R¹² are hydrogen. In certain embodiments, two of R¹⁰, R¹¹, R¹²and R¹³ are methyl and the remaining are hydrogen. For example, in someinstances, two of R¹⁰, R¹¹, R¹² and R¹³ are methyl and the remaining arehydrogen. In some instances, R¹⁰ and R¹¹ are C₁₋₆ alkyl (e.g., methyl)and R¹² and R¹³ are hydrogen. In some instances, R¹⁰ and R¹² are C₁₋₆alkyl (e.g., methyl) and R¹¹ and R¹³ are hydrogen. In some instances,R¹⁰ and R¹³ are C₁₋₆ alkyl (e.g., methyl) and R¹¹ and R¹² are hydrogen.In some instances, R¹¹ and R¹² are C₁₋₆ alkyl (e.g., methyl) and R¹⁰ andR¹³ are hydrogen. In some instances, R¹¹ and R¹³ are C₁₋₆ alkyl (e.g.,methyl) and R¹⁰ and R¹² are hydrogen. In some instances, R¹² and R¹³ areC₁₋₆ alkyl (e.g., methyl) and R¹⁰ and R¹¹ are hydrogen.

In certain embodiments, X¹ has the formula:

wherein R², R³ and R⁴ are as described above; and R¹⁰, R¹¹, R¹² and R¹³are each independently selected from hydrogen, alkyl and substitutedalkyl.

In the formula above for X¹, the substituents R², R³ and R⁴ are asdescribed above.

In certain embodiments, R¹⁰ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹⁰ is hydrogen. In certainembodiments, R¹⁰ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹⁰ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹¹ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹¹ is hydrogen. In certainembodiments, R¹¹ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹¹ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹² is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹² is hydrogen. In certainembodiments, R¹² is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹² issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹³ is selected from hydrogen, alkyl andsubstituted alkyl. In certain embodiments, R¹³ is hydrogen. In certainembodiments, R¹³ is alkyl, such as C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, butyl, pentyl or hexyl). In certain embodiments, R¹³ issubstituted alkyl, such as substituted C₁₋₆ alkyl, substituted C₁₋₃alkyl, or substituted C₁₋₂ alkyl.

In certain embodiments, R¹⁰, R¹¹, R¹² and R¹³ are each independentlyselected from hydrogen and C₁₋₆ alkyl. In certain embodiments, R¹⁰, R¹¹,R¹² and R¹³ are each hydrogen. In certain embodiments, one of R¹⁰, R¹¹,R¹² and R¹³ is C₁₋₆ alkyl and the remaining are hydrogen. For example,in some instances, one of R¹⁰, R¹¹, R¹² and R¹³ is methyl and theremaining are hydrogen. In some instances, R¹⁰ is C₁₋₆ alkyl (e.g.,methyl) and R¹¹, R¹² and R¹³ are hydrogen. In some instances, R¹¹ isC₁₋₆ alkyl (e.g., methyl) and R¹⁰, R¹² and R¹³ are hydrogen. In someinstances, R¹² is C₁₋₆ alkyl (e.g., methyl) and R¹⁰, R¹¹ and R¹³ arehydrogen. In some instances, R¹³ is C₁₋₆ alkyl (e.g., methyl) and R¹⁰,R¹¹ and R¹² are hydrogen. In certain embodiments, two of R¹⁰, R¹¹, R¹²and R¹³ are methyl and the remaining are hydrogen. For example, in someinstances, two of R¹⁰, R¹¹, R¹² and R¹³ are methyl and the remaining arehydrogen. In some instances, R¹⁰ and R¹¹ are C₁₋₆ alkyl (e.g., methyl)and R¹² and R¹³ are hydrogen. In some instances, R¹⁰ and R¹² are C₁₋₆alkyl (e.g., methyl) and R¹¹ and R¹³ are hydrogen. In some instances,R¹⁰ and R¹³ are C₁₋₆ alkyl (e.g., methyl) and R¹¹ and R¹² are hydrogen.In some instances, R¹¹ and R¹² are C₁₋₆ alkyl (e.g., methyl) and R¹⁰ andR¹³ are hydrogen. In some instances, R¹¹ and R¹³ are C₁₋₆ alkyl (e.g.,methyl) and R¹⁰ and R¹² are hydrogen. In some instances, R¹² and R¹³ areC₁₋₆ alkyl (e.g., methyl) and R¹⁰ and R¹¹ are hydrogen.

In some embodiments, the compound is a dimer. In these embodiments, R¹is R¹⁵, where R¹⁵ includes a linking group and a second compound offormula (IIa) or (IIb). In certain embodiments, the linking group is analkyl linking group, such as a C₁₋₁₀ alkyl linking group, or a C₁₋₈alkyl linking group, or a C₁₋₆ alkyl linking group, or a C₁₋₃ alkyllinking group. In certain embodiments, the linking group attaches afirst compound of formula (IIa) or (IIb) to a second compound of formula(IIa) or (IIb). In some instances, the first compound of formula (IIa)or (IIb) has one end of the linking group attached at the R¹ position,and the other end of the linking group is attached at the R¹ position ofthe second compound of formula (IIa) or (IIb). In these embodiments, thetwo compounds of formula (IIa) and/or (IIb) in the dimer are connectedto each other at their respective R¹ positions through the linkinggroup. In certain embodiments, the compound is a symmetrical dimer. Insome instances, the compound is an unsymmetrical dimer. In certainembodiments, two compounds of formula (IIa) are connected to each otherin the dimer at their respective R¹ positions through the linking group.In certain embodiments, two compounds of formula (IIb) are connected toeach other in the dimer at their respective R¹ positions through thelinking group.

In certain embodiments, the linking group is has the structure:—(CH₂)_(n)—Z_(y)—(CH₂)_(m)—, wherein

n is an integer from 1 to 6;

m is 0 or an integer from 1 to 6;

y is 0 or 1; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—.

In certain embodiments, n is an integer from 1 to 6, such as 1, 2, 3, 4,5 or 6.

In certain embodiments, m is 0 or an integer from 1 to 6. In certainembodiments, m is 0, and thus the —(CH₂)_(m)— portion of the linkinggroup is not present. In certain embodiments, m is an integer from 1 to6, such as 1, 2, 3, 4, 5 or 6.

In certain embodiments, y is 0 or 1. In certain embodiments, y is 0, andthus Z is not present. In certain embodiments, y is 1, and thus Z ispresent.

In certain embodiments, Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or—O—S(O)₂—O—. In certain embodiments, Z is O. In certain embodiments, Zis NH. In certain embodiments, Z is —O—P(O)(OH)—O—. In certainembodiments, Z is S. In certain embodiments, Z is S(O). In certainembodiments, Z is SO₂. In certain embodiments, Z is —O—S(O)₂—O—.

In certain embodiments, n is 1, m is 0 and y is 0. In certainembodiments, n is 2, m is 0 and y is 0. In certain embodiments, n is 3,m is 0 and y is 0. In certain embodiments, n is 4, m is 0 and y is 0. Incertain embodiments, n is 5, m is 0 and y is 0. In certain embodiments,n is 6, m is 0 and y is 0.

In certain embodiments, n is 1, m is 1, y is 1 and Z is O. In certainembodiments, n is 2, m is 2, y is 1 and Z is O. In certain embodiments,n is 1, m is 1, y is 1 and Z is NH. In certain embodiments, n is 2, m is2, y is 1 and Z is NH. In certain embodiments, n is 1, m is 1, y is 1and Z is —O—P(O)(OH)—O—. In certain embodiments, n is 2, m is 2, y is 1and Z is —O—P(O)(OH)—O—. In certain embodiments, n is 1, m is 1, y is 1and Z is S. In certain embodiments, n is 2, m is 2, y is 1 and Z is S.In certain embodiments, n is 1, m is 1, y is 1 and Z is S(O). In certainembodiments, n is 2, m is 2, y is 1 and Z is S(O). In certainembodiments, n is 1, m is 1, y is 1 and Z is SO₂. In certainembodiments, n is 2, m is 2, y is 1 and Z is SO₂. In certainembodiments, n is 1, m is 1, y is 1 and Z is —O—S(O)₂—O—. In certainembodiments, n is 2, m is 2, y is 1 and Z is —O—S(O)₂—O—.

In certain embodiments, n is 1, m is 1, and y is 1. As such, in certainembodiments, the compound has the formula:

wherein

X^(1a) and X^(1b) are each independently selected from H, C₁₋₆ alkyl anda progroup; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein

X^(1a) and X^(1b) are each independently selected from H, C₁₋₆ alkyl anda progroup; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein

X^(1a) and X^(1b) are each independently selected from H, C₁₋₆ alkyl anda progroup; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, n is 2, m is 2, and y is 1. As such, in certainembodiments, the compound has the formula:

wherein

X^(1a) and X^(1b) are each independently selected from H, C₁₋₆ alkyl anda progroup; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O) SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein

X^(1a) and X^(1b) are each independently selected from H, C₁₋₆ alkyl anda progroup; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O) SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, the compound has the formula:

wherein

X^(1a) and X^(1b) are each independently selected from H, C₁₋₆ alkyl anda progroup; and

Z is O, NH, —O—P(O)(OH)—O—, S, S(O) SO₂ or —O—S(O)₂—O—,

or a salt or stereoisomer thereof.

In certain embodiments, n is 1, m is 1 and y is 1. In one suchembodiment, Z is a phosphate ester and the compound has the formula:

or a salt thereof, and wherein X^(1a) and X^(1b) are each independentlyselected from H, C₁₋₆ alkyl and a progroup.

In certain embodiments, X^(1a) and X^(1b) are each independentlyselected from H, C₁₋₆ alkyl and a progroup. In certain embodiments,X^(1a) and X^(1b) are each H. In certain embodiments, one of X^(1a) andX^(1b) is H, and the other is C₁₋₆ alkyl or a progroup. In certainembodiments, X^(1a) and X^(1b) are each C₁₋₆ alkyl. In theseembodiments, the C₁₋₆ alkyl groups for X^(1a) and X^(1b) may be the sameor different. In certain embodiments, X^(1a) and X^(1b) are each aprogroup. In these embodiments, the progroups for X^(1a) and X^(1b) maybe the same or different. In certain embodiments, X^(1a) is C₁₋₆ alkyland X^(1b) is a progroup. In certain embodiments, X^(1a) is a progroupand X^(1b) is C₁₋₆ alkyl. The progroup for X^(1a) and X^(1b) aredescribed in more detail above. For example, the progroup for X^(1a) andX^(1b) may each independently be X¹ as described in more detail above.

In certain embodiments, Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or—O—S(O)₂—O—. In certain embodiments, Z is O. In certain embodiments, Zis NH. In certain embodiments, Z is —O—P(O)(OH)—O—. In certainembodiments, Z is S. In certain embodiments, Z is S(O). In certainembodiments, Z is SO₂. In certain embodiments, Z is —O—S(O)₂—O—.

In certain embodiments, the compound of formula (IIa) is a dimerselected from the following compounds:

wherein X^(1a) and X^(1b) are as described above, or a salt orstereoisomer thereof.

For example, X^(1a) and X^(1b) may each be independently selected fromH, C₁₋₆ alkyl and a progroup. In some instances, the progroup for X^(1a)and X^(1b) may each independently be X¹ as described in more detailabove.

In certain embodiments, the linking group connecting the two compoundsof formula II in a dimer may be a cleavable linking group. In someinstances, cleavage of the linking group in the dimer releases theactive agent moieties (e.g., two pharmaceutically active compounds). Forexample, a cleavable linking group may be cleaved by hydrolysis of oneor more bonds in the linking group that connect the first compound offormula (IIa) or (IIb) to the second compound of formula (IIa) or (IIb)in the dimer. In some embodiments, cleavage of the cleavable linkinggroup may occur in vivo, for instance in the gastrointestinal tract(e.g., stomach, small intestine, large intestine, etc.), or a desiredsite of action of the compound. In certain cases, compounds that includea cleavable linking group may facilitate delivery of thepharmaceutically active forms of the compound at a desired site ofaction, or after a desired amount of time after administration of thedimer (e.g., delayed release formulations, controlled releaseformulations, and the like).

Embodiments of the compounds of formulae (Ia), (Ib), (IIa) and (IIb) areshown in the following tables.

TABLE 1

Compound X¹ R¹ 1 —CH₃ H 2 —CH₃ —CH₃ 3 H H 4 H —CH₃ 5 —CH₃ —CH₂CH₃ 6 —CH₃—CH(CH₃)₂ 7 —CH₃

8 —CH₃ —CH₂C(O)NH₂ 9 —CH₃ —CH₂OCH₃ 10 —CH₃ —C(O)N(CH₃)₂ 11 —CH₃-cyclopentyl 12 —CH₃ 4-tetrahydropyranyl 13 —CH₃ —CH₂CH₂OCH₃ 14 —CH₃—CH₂C(O)OCH₃ 15 -tert-butyl —CH₃ 16 —CH₃ phenyl 17 —CH₃ 3-pyridyl 18

—CH₃ 19 —CH₃ —CH₂C(CH₃)₂OH 20 —CH₃

21 —CH₃ cyclopropyl 24 —CH₃ —CD₃ 25 —CH₃ —CD(CD₃)₂ 26 —CH₃—CH₂CH₂N(CH₃)₂

TABLE 2

Compound X¹ R¹ 22 —CH₃ —CH₂CH₃ 23 tert-butyl —CH₃

Particular compounds disclosed herein, and salts or solvates orstereoisomers thereof, include: Compound 1: methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate; Compound 2: methyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate; Compound 3:(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylic acid; Compound 4:(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylic acid;Compound 5: methyl(E)-3-(4-ethyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate; Compound 6:methyl (E)-3-(4-isopropyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 7: methyl(E)-3-(4-((3-methyloxetan-3-yl)methyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 8: methyl(E)-3-(4-(2-amino-2-oxoethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 9: methyl(E)-3-(4-(methoxymethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 10: Preparation of Methyl(E)-3-(4-(dimethylcarbamoyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 11: methyl(E)-3-(4-cyclopentyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 12: methyl(E)-3-(5-oxo-4-(tetrahydro-2H-pyran-4-yl)-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 13: methyl(E)-3-(4-(2-methoxyethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 14: methyl(E)-3-(4-(2-methoxy-2-oxoethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 15: tert-butyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate; Compound16: methyl (E)-3-(5-oxo-4-phenyl-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 17: methyl(E)-3-(5-oxo-4-(pyridin-3-yl)-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 18: 2-(2,5-dioxopyrrolidin-1-yl)ethyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate; Compound19: methyl(E)-3-(4-(2-hydroxy-2-methylpropyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 20: dimethyl3,3′-(5-oxo-1H-tetrazole-1,4(5H)-diyl)(2E,2′E)-diacrylate; Compound 21:methyl (E)-3-(4-cyclopropyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 22: methyl(Z)-3-(4-ethyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate; Compound 23:tert-butyl (Z)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 24: methyl(E)-3-(4-deuteriomethyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate;Compound 25: methyl(E)-3-(4-deuterioisopropyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylateand Compound 26: methyl(E)-3-(4-(2-(dimethylamino)ethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate.

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

In certain embodiments, the compound has the structure:

The compounds described also include isotopically labeled compoundswhere one or more atoms have an atomic mass different from the atomicmass conventionally found in nature. Examples of isotopes that may beincorporated into the compounds disclosed herein include, but are notlimited to, ²H, ³H, ¹¹C, ¹³C, ¹⁴C, ¹⁵N, ¹⁸O, ¹⁷O, etc. Thus, thedisclosed compounds may be enriched in one or more of these isotopesrelative to the natural abundance of such isotope. By way of example,deuterium (²H; D) has a natural abundance of about 0.015%. Accordingly,for approximately every 6,500 hydrogen atoms occurring in nature, thereis one deuterium atom. Specifically contemplated herein are compoundsenriched in deuterium at one or more positions. Thus, deuteriumcontaining compounds of the disclosure have deuterium at one or morepositions (as the case may be) in an abundance of greater than 0.015%.In some embodiments, one or more (e.g., 1, 2, 3, 4, 5, 6, 7 or more)hydrogen atoms of an R¹ group of any one of the subject compoundsdescribed herein are substituted with a deuterium.

Pharmaceutical Compositions

In certain embodiments, the disclosed compounds are useful for thetreatment of a disease or disorder, such as an autoimmune or aninflammatory disease or disorder. Accordingly, pharmaceuticalcompositions comprising at least one disclosed compound are alsodescribed herein. For example, the present disclosure providespharmaceutical compositions that include a pharmaceutically acceptablecarrier and a therapeutically effective amount of a compound of thepresent disclosure or a pharmaceutically acceptable salt or solvate orstereoisomer thereof.

A pharmaceutical composition that includes a subject compound may beadministered to a patient alone, or in combination with othersupplementary active agents. For example, one or more compoundsaccording to formula I or formula II can be administered to a patientwith or without supplementary active agents. By way of examplesupplementary active agents include dimethyl fumarate andmonomethylfumarate and salts thereof. The pharmaceutical compositionsmay be manufactured using any of a variety of processes, including, butnot limited to, conventional mixing, dissolving, granulating,dragee-making, levigating, emulsifying, encapsulating, entrapping,lyophilizing, and the like. The pharmaceutical composition can take anyof a variety of forms including, but not limited to, a sterile solution,suspension, emulsion, spray dried dispersion, lyophilisate, tablet,microtablets, pill, pellet, capsule, powder, syrup, elixir or any otherdosage form suitable for administration.

A subject compound may be administered to a subject using any convenientmeans capable of resulting in the desired reduction in disease conditionor symptom. Thus, a subject compound can be incorporated into a varietyof formulations for therapeutic administration. More particularly, asubject compound can be formulated into pharmaceutical compositions bycombination with appropriate pharmaceutically acceptable carriers ordiluents, and may be formulated into preparations in solid, semi-solid,liquid or gaseous forms, such as tablets, capsules, powders, granules,ointments, solutions, suppositories, injections, inhalants, aerosols,and the like.

Formulations for pharmaceutical compositions are described in, forexample, Remington's Pharmaceutical Sciences, by E. W. Martin, MackPublishing Co., Easton, Pa., 19th Edition, 1995, which describesexamples of formulations (and components thereof) suitable forpharmaceutical delivery of disclosed compounds. Pharmaceuticalcompositions that include at least one of the subject compounds can beformulated for use in human or veterinary medicine. Particularformulations of a disclosed pharmaceutical composition may depend, forexample, on the mode of administration and/or on the location of thesubject to be treated. In some embodiments, formulations include apharmaceutically acceptable carrier in addition to at least one activeingredient, such as a subject compound. In other embodiments, othermedicinal or pharmaceutical agents, for example, with similar, relatedor complementary effects on the disease or condition being treated canalso be included as active ingredients in a pharmaceutical composition.

Pharmaceutically acceptable carriers useful for the disclosed methodsand compositions may depend on the particular mode of administrationbeing employed. For example, parenteral formulations may includeinjectable fluids, such as, but not limited to, pharmaceutically andphysiologically acceptable fluids such as water, physiological saline,balanced salt solutions, aqueous dextrose, glycerol or the like as avehicle. For solid compositions (e.g., powder, pill, tablet, or capsuleforms), non-toxic solid carriers can include, for example,pharmaceutical grades of mannitol, lactose, starch, or magnesiumstearate. In addition to biologically neutral carriers, pharmaceuticalcompositions to be administered can optionally contain minor amounts ofnon-toxic auxiliary substances (e.g., excipients), such as wetting oremulsifying agents, preservatives, and pH buffering agents and the like;for example, sodium acetate or sorbitan monolaurate. Other examples ofexcipients include, nonionic solubilizers, such as cremophor, orproteins, such as human serum albumin or plasma preparations.

Some examples of materials which can serve aspharmaceutically-acceptable carriers include: (1) sugars, such aslactose, glucose and sucrose; (2) starches, such as corn starch andpotato starch; (3) cellulose, and its derivatives, such as sodiumcarboxymethyl cellulose, ethyl cellulose and cellulose acetate; (4)powdered tragacanth; (5) malt; (6) gelatin; (7) talc; (8) excipients,such as cocoa butter and suppository waxes; (9) oils, such as peanutoil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil andsoybean oil; (10) glycols, such as propylene glycol; (11) polyols, suchas glycerin, sorbitol, mannitol, and polyethylene glycol; (12) esters,such as ethyl oleate and ethyl laurate; (13) agar; (14) bufferingagents, such as magnesium hydroxide and aluminum hydroxide; (15) alginicacid; (16) water (e.g., pyrogen-free water); (17) isotonic saline; (18)Ringer's solution; (19) ethyl alcohol; (20) pH buffered solutions; (21)polyesters, polycarbonates and/or polyanhydrides; and (22) othernon-toxic compatible substances employed in pharmaceutical formulations.

The disclosed pharmaceutical compositions may be formulated as apharmaceutically acceptable salt of a disclosed compound. Examples ofpharmaceutically acceptable salts include non-toxic salts of a free baseform of a compound that possesses the desired pharmacological activityof the free base. These salts may be derived from inorganic or organicacids. Non-limiting examples of suitable inorganic acids arehydrochloric acid, nitric acid, hydrobromic acid, sulfuric acid,hydroiodic acid, and phosphoric acid. Non-limiting examples of suitableorganic acids are acetic acid, propionic acid, glycolic acid, lacticacid, pyruvic acid, malonic acid, succinic acid, malic acid, maleicacid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamicacid, mandelic acid, methanesulfonic acid, ethanesulfonic acid, methylsulfonic acid, salicylic acid, formic acid, trichloroacetic acid,trifluoroacetic acid, gluconic acid, asparagic acid, aspartic acid,benzenesulfonic acid, para-toluenesulfonic acid, naphthalenesulfonicacid, combinations thereof, and the like. In certain embodiments, thepharmaceutically acceptable salt includes formic acid. Other examples ofpharmaceutically acceptable salts include non-toxic salts of a free acidform of compounds according to formula I or formula II. Such salts arederived from inorganic or organic bases. Pharmaceutically acceptablebase addition salts include those derived from inorganic bases such assodium, potassium, lithium, ammonium, calcium, magnesium, iron, zinc,copper, manganese, aluminum salts, combinations thereof, and the like.Examples of salts are the ammonium, potassium, sodium, calcium, andmagnesium salts. Salts of the presently disclosed compounds can bederived from pharmaceutically acceptable organic non-toxic basesincluding, but not limited to, salts of primary, secondary, and tertiaryamines, substituted amines including naturally occurring substitutedamines, cyclic amines and basic ion exchange resins, such asisopropylamine, trimethylamine, diethylamine, triethylamine,tripropylamine, ethanolamine, 2-dimethylaminoethanol,2-diethylaminoethanol, 2-amino-2-hydroxymethyl-propane-1,3-diol (“Tris”salt), dicyclohexylamine, lysine, arginine, histidine, caffeine,procaine, hydrabamine, choline, betaine, ethylenediamine, glucosamine,methylglucamine, theobromine, purines, piperazine, piperidine,N-ethylpiperidine, combinations thereof, and the like. Pharmaceuticallyacceptable salts are described further in S. M. Berge, et al.,“Pharmaceutical Salts,” J. Pharm. Sci., 1977; 66:1-19 and Remington'sPharmaceutical Sciences, 19th Edition, Mack Publishing Company, Easton,Pa., 1995.

A subject compound can be used alone or in combination with appropriateadditives to make tablets, powders, granules or capsules, for example,with conventional additives, such as lactose, mannitol, corn starch orpotato starch; with binders, such as crystalline cellulose, cellulosederivatives, acacia, corn starch or gelatins; with disintegrators, suchas corn starch, potato starch or sodium carboxymethylcellulose; withlubricants, such as talc or magnesium stearate; and if desired, withdiluents, buffering agents, moistening agents, preservatives andflavoring agents. Such preparations can be used for oral administration.

A subject compound can be formulated into preparations for injection bydissolving, suspending or emulsifying the compound in an aqueous ornonaqueous solvent, such as vegetable or other similar oils, syntheticaliphatic acid glycerides, esters of higher aliphatic acids or propyleneglycol; and if desired, with conventional additives such assolubilizers, isotonic agents, suspending agents, emulsifying agents,stabilizers and preservatives. The preparation may also be emulsified orthe active ingredient encapsulated in liposome vehicles. Formulationssuitable for injection can be administered by an intravitreal,intraocular, intramuscular, subcutaneous, sublingual, or other route ofadministration, e.g., injection into the gum tissue or other oraltissue. Such formulations are also suitable for topical administration.

In some embodiments, a subject compound can be delivered by a continuousdelivery system. The term “continuous delivery system” is usedinterchangeably herein with “controlled delivery system” and encompassescontinuous (e.g., controlled) delivery devices (e.g., pumps) incombination with catheters, injection devices, and the like, a widevariety of which are known in the art.

A subject compound can be utilized in aerosol formulation to beadministered via inhalation. A subject compound can be formulated intopressurized acceptable propellants such as dichlorodifluoromethane,propane, nitrogen and the like.

Furthermore, a subject compound can be made into suppositories by mixingwith a variety of bases such as emulsifying bases or water-solublebases. A subject compound can be administered rectally via asuppository. The suppository can include vehicles such as cocoa butter,carbowaxes and polyethylene glycols, which melt at body temperature, yetare substantially solid at room temperature.

The term “unit dosage form,” as used herein, refers to physicallydiscrete units suitable as unitary dosages for human and animalsubjects, each unit containing a predetermined quantity of a subjectcompound calculated in an amount sufficient to produce the desiredeffect in association with a pharmaceutically acceptable diluent,carrier or vehicle. The specifications for a subject compound depend onthe particular compound employed and the effect to be achieved, and thepharmacodynamics associated with each compound in the host.

The dosage form of a disclosed pharmaceutical composition may bedetermined by the mode of administration chosen. For example, inaddition to injectable fluids, topical or oral dosage forms may beemployed. Topical preparations may include eye drops, ointments, spraysand the like. Oral formulations may be liquid (e.g., syrups, solutionsor suspensions), or solid (e.g., powders, pills, tablets, or capsules).Methods of preparing such dosage forms are known, or will be apparent,to those skilled in the art.

Certain embodiments of the pharmaceutical compositions that include asubject compound may be formulated in unit dosage form suitable forindividual administration of precise dosages. The amount of activeingredient administered may depend on the subject being treated, theseverity of the affliction, and the manner of administration, and isknown to those skilled in the art. In certain instances, the formulationto be administered contains a quantity of the compounds disclosed hereinin an amount effective to achieve the desired effect in the subjectbeing treated.

Each therapeutic compound can independently be in any dosage form, suchas those described herein, and can also be administered in various ways,as described herein. For example, the compounds may be formulatedtogether, in a single dosage unit (that is, combined together in oneform such as capsule, tablet, powder, or liquid, etc.) as a combinationproduct. Alternatively, when not formulated together in a single dosageunit, an individual subject compound may be administered at the sametime as another therapeutic compound or sequentially, in any orderthereof.

A disclosed compound can be administered alone, as the sole activepharmaceutical agent, or in combination with one or more additionalcompounds of the present disclosure or in conjunction with other agents.When administered as a combination, the therapeutic agents can beformulated as separate compositions that are administered simultaneouslyor at different times, or the therapeutic agents can be administeredtogether as a single composition combining two or more therapeuticagents. Thus, the pharmaceutical compositions disclosed hereincontaining a compound of the present disclosure optionally include othertherapeutic agents. Accordingly, certain embodiments are directed tosuch pharmaceutical compositions, where the composition further includesa therapeutically effective amount of an agent selected as is known tothose of skill in the art.

Methods of Administration

The subject compounds find use for treating a disease or disorder in asubject, such as an autoimmue or an inflammatory disease or disorder.The route of administration may be selected according to a variety offactors including, but not limited to, the condition to be treated, theformulation and/or device used, the patient to be treated, and the like.Routes of administration useful in the disclosed methods include but arenot limited to oral and parenteral routes, such as intravenous (iv),intraperitoneal (ip), rectal, topical, ophthalmic, nasal, andtransdermal. Formulations for these dosage forms are described herein.

An effective amount of a subject compound may depend, at least, on theparticular method of use, the subject being treated, the severity of theaffliction, and the manner of administration of the therapeuticcomposition. A “therapeutically effective amount” of a composition is aquantity of a specified compound sufficient to achieve a desired effectin a subject (e.g., patient) being treated. For example, this may be theamount of a subject compound necessary to prevent, inhibit, reduce orrelieve a disease or disorder in a subject, such as an autoimmue or aninflammatory disease or disorder. Ideally, a therapeutically effectiveamount of a compound is an amount sufficient to prevent, inhibit, reduceor relieve a disease or disorder in a subject without causing asubstantial cytotoxic effect on host cells in the subject.

Therapeutically effective doses of a subject compound or pharmaceuticalcomposition can be determined by one of skill in the art, with a goal ofachieving local (e.g., tissue) concentrations that are at least as highas the EC₅₀ of an applicable compound disclosed herein.

An example of a dosage range is from 0.1 to 200 mg/kg body weight orallyin single or divided doses. In some embodiments, a dosage range is from1.0 to 100 mg/kg body weight orally in single or divided doses,including from 1.0 to 50 mg/kg body weight, from 1.0 to 25 mg/kg bodyweight, from 1.0 to 10 mg/kg body weight (assuming an average bodyweight of approximately 70 kg; values may be adjusted accordingly forpersons weighing more or less than average). For oral administration,the compositions are, for example, provided in the form of a tabletcontaining from about 10 to about 1000 mg of the active ingredient, suchas 25 to 750 mg, or 50 to 500 mg, for example 75 mg, 100 mg, 200 mg, 250mg, 400 mg, 500 mg, 600 mg, 750 mg, or 1000 mg of the active ingredientfor the symptomatic adjustment of the dosage to the subject beingtreated. In certain embodiments of an oral dosage regimen, a tabletcontaining from 500 mg to 1000 mg active ingredient is administered once(e.g., a loading dose) followed by administration of ½ (i.e., half)dosage tablets (e.g., from 250 to 500 mg) each 6 to 24 hours for 3 daysor more.

The specific dose level and frequency of dosage for any particularsubject may be varied and may depend upon a variety of factors,including the activity of the subject compound, the metabolic stabilityand length of action of that compound, the age, body weight, generalhealth, sex and diet of the subject, mode and time of administration,rate of excretion, drug combination, and severity of the condition ofthe host undergoing therapy.

Embodiments of the present disclosure also include combinations of oneor more disclosed compounds with one or more other agents or therapiesuseful in the treatment of a disease or disorder. In certain instances,the disease or disorder is an autoimmue or an inflammatory disease ordisorder. In certain instances, the disease or disorder is psoriasis,such as plaque psoriasis. In certain instances, the disease or disorderis multiple sclerosis. For example, one or more disclosed compounds maybe administered in combination with therapeutically effective doses ofother medicinal and pharmaceutical agents, or in combination othernon-medicinal therapies, such as hormone (e.g., corticosteroids) orradiation therapy (e.g., phototherapy). The term “administration incombination with” refers to both concurrent and sequentialadministration of the active agents.

Methods of Treatment

The subject compounds are useful for treating a disease or disorder,such as an autoimmue or an inflammatory disease or disorder, in asubject in need of treatment. In certain instances, the disease ordisorder is an autoimmue or an inflammatory disease or disorder. Incertain instances, the disease or disorder is psoriasis, such as plaquepsoriasis. In certain instances, the disease or disorder is multiplesclerosis. Other diseases that can be treated with the compoundsdisclosed herein include pulmonary arterial hypertension (PAH),non-alcoholic and alcoholic steatohepatitis, traumatic brain injury,radiation exposure and exposure to toxic chemicals such as cyanide.

Accordingly, the present disclosure provides methods of treating aninflammatory disease in a subject by administering an effective amountof a subject compound, including a salt or solvate or stereoisomerthereof, so as to treat inflammation. For example, the presentdisclosure provides a method of treating an inflammatory disease in asubject. In certain embodiments, the method includes administering tothe subject (e.g., patient) a compound of the present disclosure, or asalt or solvate or stereoisomer thereof.

In addition, the present disclosure also provides methods of treating anautoimmune disease in a subject by administering to the subject aneffective amount of a subject compound, including a salt or solvate orstereoisomer thereof, so as to treat the autoimmune disease. Forexample, the present disclosure also provides a method of treating anautoimmune disease in a subject. In certain embodiments, the methodincludes administering to the subject (e.g., patient) a compound of thepresent disclosure, or a salt or solvate or stereoisomer thereof.

In some embodiments, the subject compounds are resistant to degradationin vivo. In certain embodiments, the subject compound is stable in vivo.In certain instances, the compound includes an R¹ group (e.g., asdescribed herein) that is attached to a core tetrazolone ring of thecompound via a covalent bond that is not cleaved in vivo. In certaincases, the subject compound has an extended in vivo half life, e.g., ahalf life of 4 hours or more, such as 6 hours or more, 8 hours or more,12 hours or more, 1 day or more, 2 days or more, 3 days or more, 4 daysor more, 5 days or more, 6 days or more, 1 week or more, 2 weeks ormore, 4 weeks or more, or even more. As used herein, the term “in vivohalf life” refers to the time that it takes for the concentration inblood plasma of a substance of interest to reach one-half of itssteady-state value.

Diseases or conditions for treatment according to the present disclosureinclude, but are not limited to, psoriasis, multiple sclerosis,inflammatory bowel disease, asthma, chronic obstructive pulmonarydisease, and arthritis. For example, diseases or conditions fortreatment according to the present disclosure include, but are notlimited to, immunological, autoimmune, and/or inflammatory diseasesincluding: psoriasis such as plaque psoriasis; asthma; chronicobstructive pulmonary diseases (COPD) such as bronchitis, emphysema, aswell as other lung disorders such as asbestosis, pneumoconiosis, andpulmonary neoplasms; arthritis such as inflammatory arthritis, includingrheumatoid arthritis, juvenile rheumatoid arthritis (juvenile idiopathicarthritis), psoriatic arthritis, and ankylosing spondylitis producejoint inflammation; cardiac insufficiency including left ventricularinsufficiency, myocardial infarction and angina pectoris; mitochondrialand neurodegenerative diseases such as Parkinson's disease, Alzheimer'sdisease, Huntington's disease, amyotrophic lateral sclerosis (ALS or LouGehrig's Disease), retinopathia pigmentosa and mitochondrialencephalomyopathy; transplantation rejection; autoimmune diseasesincluding multiple sclerosis, ischemia and reperfusion injury,AGE-induced genome damage; inflammatory bowel diseases (IBD) such asCrohn's disease and ulcerative colitis; and NF-κB mediated diseases.

Further diseases or conditions for treatment according to the presentdisclosure include, but are not limited to, rheumatica, granulomaannulare, lupus, autoimmune carditis, eczema, sarcoidosis, andautoimmune diseases including acute disseminated encephalomyelitis,Addison's disease, alopecia areata, ankylosing spondylitis,antiphospholipid antibody syndrome, autoimmune hemolytic anemia,autoimmune hepatitis, autoimmune inner ear disease, bullous pemphigoid,Behcet's disease, celiac disease, Chagas disease, chronic obstructivepulmonary disease, Crohn's disease, dermatomyositis, diabetes mellitustype I, endometriosis, Goodpasture's syndrome, Graves' disease,Guillain-Barre syndrome, Hashimoto's disease, hidradenitis suppurativea,Kawasaki disease, IgA neuropathy, idiopathic thrombocytopenic purpura,interstitial cystitis, lupus erythematosus, mixed connective tissuedisease, morphea, multiple sclerosis, myasthenia gravis, narcolepsy,neuromyotonia, pemphigus vulgaris, pernicious anaemia, psoriasis,psonatic arthritis, polymyositis, primary biliary cirrhosis, rheumatoidarthritis, schizophrena, scleroderma, Sjogren's syndrome, stiff personsyndrome, temporal arteritis, ulcerative colitis, vasculitis, vitiligo,and Wegener's granulomatosis.

Additional diseases or conditions for treatment according to the presentdisclosure include, but are not limited to, necrobiosis lipodica,granuloma annulare, sarcoidosis, alopecia areata, cheilitisgranulomatosa, recurrent oral aphthae, non-infectious chronic uveitis,pityriasis rubra pilaris, annular elastolytic giant cell granuloma, andthe like. Diseases or conditions for treatment according to the presentdisclosure also include Huntington's disease, malaria, HIV,HIV-associated neurodegenerative disorders, bronchial asthma, myocardialinfarction, chronic obstructive pulmonary disease, HSV1 keratitis, andimmunosuppression due to organ transplantation.

In certain embodiments, the subject compounds are useful for treating adisease or disorder, such as cell proliferative disorders. Cellproliferative disorders treatable with the subject compound disclosedherein relate to any disorder characterized by aberrant cellproliferation. These include various tumors and cancers, benign ormalignant, metastatic or non-metastatic. Specific properties of cancers,such as tissue invasiveness or metastasis, can be targeted using themethods described herein. Cell proliferative disorders include a varietyof cancers, including, among others, breast cancer, colon cancer,melanoma, glioblastoma, ovarian cancer, renal cancer, gastrointestinalcancer, kidney cancer, bladder cancer, pancreatic cancer, lung squamouscarcinoma, and adenocarcinoma.

Compounds of the present disclosure may also find use as research tools.Accordingly, the present disclosure also provides for a method for usinga compound of the present disclosure or a salt or solvate orstereoisomer thereof as a research tool for studying a biological systemor sample, or for discovering new chemical compounds having use fortreating a an autoimmue or an inflammatory disease or disorder in asubject.

Embodiments are also directed to a compound of the present disclosure ora salt or solvate or stereoisomer thereof, for use in therapy or as amedicament. For instance, embodiments include the use of a compound ofthe present disclosure or a salt or solvate or stereoisomer thereof, forthe manufacture of a medicament; for example, for the manufacture of amedicament for the treatment of an autoimmune or inflammatory disease ordisorder. In some cases, the embodiments are also directed to the use ofa compound of the present disclosure or a salt or solvate orstereoisomer thereof for the manufacture of a medicament for thetreatment of an autoimmune disease, such as multiple sclerosis. Theembodiments are also directed to the use of a compound of the presentdisclosure or a salt or solvate or stereoisomer thereof for themanufacture of a medicament for the treatment of an inflammatory diseaseor disorder, such as psoriasis. Further diseases or conditions fortreatment according to the present disclosure are discussed above.

Characterization of Functional Properties

The following are examples of assays useful in characterizing activitiesof a compound of the present disclosure.

A. In Vitro

1. Glutathione Depletion Assay

In one aspect the present compounds exert their therapeutic effects byacting as a Michael acceptor for reactive thiol groups in vivo. See, forexample, Lehmann et al. Dimethyfumarate Induces Immunosuppression viaGlutathione Depletion and Subsequent Induction of Heme Oxygenase 1,Journal of Investigative Dermatology (2007) 127, 835-845. Accordingly,the present compounds may be assessed in vitro by reaction withglutathione as follows:

A mixture of dimethylfumarate (5.2 mg, 3.6 mmol) and reduced glutathione(22.4 mg, 7.3 mmol; 2 equiv.) in d₆-DMSO (1.2 mL) were combined in ascrew-top vial and the mixture was stirred at 35° C. (with the topsecurely fastened). Aliquots of sample were removed at intermittenttimepoints and a ¹H NMR taken [note: after analysis by ¹H NMR, thesample can be returned to the heated vial and reaction continued). ¹HNMR indicates majority reaction with glutathione (by Michael addition tothe double bond) after 3 hr, and complete reaction by 27 hr.

The above reaction was repeated using monomethylfumarate (11.4 mg, 8.8mmol) and reduced glutathione (55.5 mg, 18.0 mmol) in d₆-DMSO (3.0 mL)at 35° C. As judged by ¹H NMR, majority reaction was observed by 27 hr.

The above reaction was repeated using methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (6.2 mg, 3.6 mmol)and reduced glutathione (22.4 mg, 7.2 mmol) in d₆-DMSO (1.2 mL) at 35°C. As judged by ¹H NMR, majority reaction was observed by 30 hr.

The above reaction was repeated using methyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (6.6 mg, 3.6mmol) and reduced glutathione (22.4 mg, 7.2 mmol) in d₆-DMSO (1.2 mL) at35° C. As judged by ¹H NMR, majority reaction was observed by 30 hr.

In all the above cases, dis-appearance of the alkene proton signals fromthe starting material are used to determine the extent of Michaelreaction with glutathione.

As would be understood by those of skill in the art, the aboveexperiments can be repeated by varying the equivalents of reducedglutathione (0.5 to 2 equivalents); the reactions can also be run in amixture of d₆-DMSO and D₂O; and the temperature of the reaction can alsobe varied from room temperature to 35° C. (35° C. being used to mimicbody temperature). As used herein “majority reaction” means a greaterthan 50% reduction in alkene proton signal as observed by ¹H NMR.

Other in vitro assays well known to those of skill in the art can beused to demonstrate the anti-inflammatory efficacy of the presentcompounds. For example, certain compounds blocked production of theinflammatory cytokine IL-23 in THP 1 cells stimulated with LPS.

B. In Vivo

1. Mouse Experimental Autoimmune Encephalomyelitis Assay

The in vivo efficacy of a compound towards autoimmune diseases can bedemonstrated in a mouse model of experimental autoimmuneencephalomyelitis (EAE).

Model Description:

EAE is a useful model for multiple sclerosis (MS), an autoimmune diseaseof the CNS that is caused by immune-cell infiltration of the CNS whitematter. Inflammation and subsequent destruction of myelin causeprogressive paralysis. Like the human disease, EAE is associated withperipheral activation of T cells autoreactive with myelin proteins, suchas myelin basic protein (MBP), proteolipid protein (PLP), or myelinoligodendrocyte protein (MOG). Activated neuroantigen-specific T cellspass the blood-brain barrier, leading to focal mononuclear cellinfiltration and demyelination. EAE can be induced in susceptible mousestrains by immunization with myelin-specific proteins in combinationwith adjuvant. In the SJL mouse model used in these studies, hind limband tail paralysis is apparent by Day 10 after immunization, the peak ofdisease severity can be observed between Days 10 and 14, and a cycle ofpartial spontaneous remission followed by relapse can be observed up toDay 35. The results can demonstrate the potential of a compound tosuppress disease severity and prevent relapse of disease symptoms thatmay be the result of FcγR-mediated cytokine release from immune cells.

Study Protocol:

In the SJL murine model of EAE, each mouse is sensitized withproteolipid protein (PLP)/complete Freund's adjuvant (CFA). (150 μgPLP₁₃₉₋₁₅₁ with 200 μg CFA in 0.05 ml of homogenate on four sites ofhind flank for a total of 0.2 ml emulsion is used to induce EAE). In asuppression protocol, either vehicle or various doses of a test compoundare administered via oral gavage starting on the day of immunization(Day 0). In a treatment protocol, at onset of disease, animals areseparated to achieve groups with a similar mean clinical score at onsetand administered vehicle or various dose frequencies of test compoundsvia oral gavage. In both protocols, clinical scores are monitored daily,and body weights are measured twice weekly.

Determination of Results:

By 10 days after PLP immunization, SJL mice can develop clinical EAE, asevidenced by an increase in their mean clinical scores. The paralyticscore can gradually increase in the animals treated with vehicle onlyfrom the day of immunization (Day 0), and by Day 14 the mean score canreach a peak of about 5.1. At disease peak (e.g., Day 14), the meanclinical score in animals treated with either daily or twice daily canbe significantly reduced. By Day 16, animals can exhibit a partialremission of mean clinical severity, which is a characteristic of theSJL model. The lower clinical scores in animals treated twice daily witha test compound can remain significant throughout the experiment untilthe animals are sacrificed on Day 30. These lower scores throughout thetreatment period are reflected in the significantly lower cumulativedisease index (CDI) and increase in cumulative weight index (CWI).

SJL mice treated with a test compound at disease onset (e.g., Day 11)can show a significant decrease in CDI. Further, there can be a decreasein the number of relapses in animals treated with a test compoundcompared with the number of relapses in animals treated with vehicle.

2. Experimental Autoimmune Encephalomyelitis Animal Model

The in vivo therapeutic efficacy of a compound for treating autoimmunediseases, such as multiple sclerosis, can be assessed in an experimentalautoimmune encephalomyelitis (EAE) animal model.

Animals and EAE Induction:

Female C57BL/6 mice, 8-10 weeks old are immunized subcutaneously in theflanks and mid-scapular region with 200 μg of myelin oligodendrocyteglycoprotein peptide (MOG₃₅₋₅₅) emulsified (1:1 volume ratio) withcomplete Freund's adjuvant (CFA) (containing 4 mg/mL Mycobacteriumtuberculosis). The emulsion is prepared by the syringe-extrusion methodwith two glass Luer-Lock syringes connected by a 3-way stopcock. Miceare also given an intraperitoneal injection of 200 ng pertussis toxin onthe day of immunization and on day two post immunization. Mice areweighed and examined daily for clinical signs of experimental autoimmuneencephalomyelitis (EAE). Food and water is provided ad libitum and onceanimals start to show disease, food is provided on the cage bottom.

Treatment Protocol:

Solutions containing various concentrations of a test compound areadministered by oral gavage twice daily to different treatment groupsstarting from day 3 post-immunization until termination. Dexamethasoneis dissolved in 1×PBS buffer (1 mg/kg) and administered subcutaneouslyonce daily.

Clinical Evaluation:

Mice are scored daily beginning on day 7 post immunization. The clinicalscoring scale is as follows: 0=normal; 1=limp tail or hind limb weakness(defined by foot slips between bars of cage top while walking); 2=limptail and hind limb weakness; 3=partial hind limb paralysis (defined asno weight bearing on hind limbs but can still move one or both hindlimbs to some extent); 4=complete hind limb paralysis; 5=moribund state(includes forelimb paralysis) or death. In some embodiments, compound 1(methyl (E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate)significantly prevents the onset of disease paralysis when dosed at 60mg/kg beginning on the day of immunization.

3. Animal Model to Assess Therapeutic Efficacy in Treating Psoriasis

The in vivo therapeutic efficacy of a compound for treating psoriasiscan be assessed in an experimental animal model. For example, thesevere, combined immunodeficient (SCID) mouse model can be used toevaluate the efficacy of compounds for treating psoriasis in humans.

SCID mice are used as tissue recipients. One biopsy for each normal orpsoriatic volunteer is transplanted onto the dorsal surface of arecipient mouse. Treatment is initiated 1 to 2 weeks aftertransplantation. Animals with the human skin transplants are dividedinto treatment groups. Animals are treated twice daily for 14 days. Atthe end of treatment, animals are photographed and then euthanized. Thetransplanted human tissue along with the surrounding mouse skin issurgically removed and fixed in 10% formalin and samples obtained formicroscopy. Epidermal thickness is measured. Tissue sections are stainedwith an antibody to the proliferation-associated antigen Ki-67 and withan anti-human CD3⁺ monoclonal antibody to detect human T lymphocytes inthe transplanted tissue. Sections are also probed with antibodies toc-myc and β-catenin. A positive response to treatment is reflected by areduction in the average epiderma thickness of the psoriatic skintransplants. A positive response is also associated with reducedexpression of Ki-67 in keratinocytes.

4. Animal Model to Assess Therapeutic Efficacy in Treating MultipleSclerosis

The in vivo therapeutic efficacy of a compound for treating multiplesclerosis can be assessed in an experimental animal model.

Experiments are conducted on female C57BL/6 mice aged 4-6 weeks andweighing 17-20 g. Experimental autoimmune encephalomyelitis (EAE) isactively induced using ≧95% pure synthetic myelin oligodendrocyteglycoprotein peptide 35-55 (MOG₃₅₋₅₅, MEVGWYRSPFSRVVHLYRNGK) (SEQ ID NO:1). Each mouse is anesthetized and receives 200 μg of MOG peptide and 15μg of Saponin extract from Quilija bark emulsified in 100 μL ofphosphate-buffered saline. A 25 μL volume is injected subcutaneouslyover four flank areas. Mice are also intraperitoneally injected with 200ng of pertussis toxin in 200 μL of PBS. A second, identical injection ofpertussis toxin is given after 48 h.

A test compound is administered at varying doses. Control animalsreceive 25 μL of DMSO. Daily treatment extends from day 26 to day 36post-immunization. Clinical scores are obtained daily from day 0post-immunization until day 60. Clinical signs are scored using thefollowing protocol: 0, no detectable signs; 0.5, distal tail limpness,hunched appearance and quiet demeanor; 1, completely limp tail; 1.5,limp tail and hindlimb weakness (unsteady gait and poor grip withhindlimbs); 2, unilateral partial hindlimb paralysis; 2.5, bilateralhindlimb paralysis; 3, complete bilateral hindlimb paralysis; 3.5,complete hindlimb paralysis and unilateral forelimb paralysis; 4, totalparalysis of hindlimbs and forelimbs.

Inflammation and demyelination are assessed by histology on sectionsfrom the CNS of EAE mice. Mice are euthanized after 30 or 60 days andwhole spinal cords are removed and placed in 0.32 M sucrose solution at4° C. overnight. Tissues are prepared and sectioned. Luxol fast bluestain is used to observe areas of demyelination. Haematoxylin and eosinstaining is used to highlight areas of inflammation by darkly stainingthe nuclei of mononuclear cells. Immune cells stained with H&E arecounted in a blinded manner under a light microscope. Sections areseparated into gray and white matter and each sector is counted manuallybefore being combined to give a total for the section. T cells areimmunolabeled with anti-CD3⁺ monoclonal antibody. After washing,sections are incubated with goat anti-rat HRP secondary antibody.Sections are then washed and counterstained with methyl green.Splenocytes isolated from mice at 30 and 60 days post-immunization aretreated with lysis buffer to remove red blood cells. Cells are thenresuspended in PBS and counted. Cells at a density of about 3×10⁶cells/mL are incubated overnight with 20 μg/mL of MOG peptide.Supernatants from stimulated cells are assayed for IFN-γ protein levelsusing an appropriate mouse IFN-γ immunoassay system.

Research Applications

Since subject compounds find use for the treatment of autoimmune andinflammatory diseases and disorders, such compounds are also useful asresearch tools. The present disclosure also provides a method for usingthe subject compounds as a research tool for studying a biologicalsystem or sample, or for discovering new chemical compounds that can beused for the treatment of autoimmune and inflammatory diseases anddisorders, such as psoriasis or multiple sclerosis.

The disclosure provides for a method of studying a biological system orsample known to be associated with an autoimmune or inflammatory diseaseor disorder, the method comprising: (a) contacting the biological samplewith a compound of the present disclosure or a salt or solvate orstereoisomer thereof; and (b) determining the efficacy of the compoundon treating the biological sample.

Any suitable biological sample can be employed in such studies which canbe conducted either in vitro or in vivo. Representative biologicalsamples suitable for such studies include, but are not limited to,cells, cellular extracts, plasma membranes, tissue samples, isolatedorgans, mammals (such as mice, rats, guinea pigs, rabbits, dogs, pigs,humans, and so forth), and the like, with mammals being of particularinterest.

When used as a research tool, a biological sample is typically contactedwith a pharmaceutically effective amount of a subject compound. Afterthe biological sample is exposed to the compound, the effects of thecompound are determined using conventional procedures and equipment,such as the assays disclosed herein. Exposure encompasses contacting thebiological sample with the compound or administering the compound to asubject. The determining step can involve measuring a response (aquantitative analysis) or can involve making an observation (aqualitative analysis). Measuring a response involves, for example,determining the effects of the compound on the biological sample usingconventional procedures and equipment, such as radioligand bindingassays and measuring ligand-mediated changes in functional assays. Theassay results can be used to determine the activity level as well as theamount of compound necessary to achieve the desired result, that is, apharmaceutically effective amount.

Additionally, the subject compounds can be used as research tools forevaluating other chemical compounds, and thus are also useful inscreening assays to discover, for example, new compounds useful for thetreatment of an autoimmune or inflammatory disease or disorder. In thismanner, a subject compound can be used as a standard in an assay toallow comparison of the results obtained with a test compound and withthe subject compounds to identify those test compounds that have aboutequal or superior activity, if any. For example, EC₅₀ data for a testcompound or a group of test compounds is compared to the EC₅₀ data for asubject compound to identify those test compounds that have the desiredproperties, for example, test compounds having an EC₅₀ about equal orsuperior to a subject compound, if any.

This aspect includes, as separate embodiments, both the generation ofcomparison data (using the appropriate assays) and the analysis of testdata to identify test compounds of interest. Thus, a test compound canbe evaluated in a biological assay, by a method comprising the steps of:(a) conducting a biological assay with a test compound to provide afirst assay value; (b) conducting the biological assay with a subjectcompound to provide a second assay value; where step (a) is conductedeither before, after or concurrently with step (b); and (c) comparingthe first assay value from step (a) with the second assay value fromstep (b). The assays that can be used for generation of comparison dataare disclosed herein, such as the mouse EAE assays.

General Synthetic Procedures

Many general references providing commonly known chemical syntheticschemes and conditions useful for synthesizing the disclosed compoundsare available (see, e.g., Smith and March, March's Advanced OrganicChemistry: Reactions, Mechanisms, and Structure, Fifth Edition,Wiley-Interscience, 2001; or Vogel, A Textbook of Practical OrganicChemistry, Including Qualitative Organic Analysis, Fourth Edition, NewYork: Longman, 1978).

Compounds as described herein can be purified by any purificationprotocol known in the art, including chromatography, such as HPLC,preparative thin layer chromatography, flash column chromatography andion exchange chromatography. Any suitable stationary phase can be used,including normal and reversed phases as well as ionic resins. In certainembodiments, the disclosed compounds are purified via silica gel and/oralumina chromatography. See, e.g., Introduction to Modern LiquidChromatography, 2nd Edition, ed. L. R. Snyder and J. J. Kirkland, JohnWiley and Sons, 1979; and Thin Layer Chromatography, ed E. Stahl,Springer-Verlag, New York, 1969.

During any of the processes for preparation of the subject compounds, itmay be necessary and/or desirable to protect sensitive or reactivegroups on any of the molecules concerned. This may be achieved by meansof conventional protecting groups as described in standard works, suchas J. F. W. McOmie, “Protective Groups in Organic Chemistry”, PlenumPress, London and New York 1973, in T. W. Greene and P. G. M. Wuts,“Protective Groups in Organic Synthesis”, Third edition, Wiley, New York1999, in “The Peptides”; Volume 3 (editors: E. Gross and J. Meienhofer),Academic Press, London and New York 1981, in “Methoden der organischenChemie”, Houben-Weyl, 4^(th) edition, Vol. 15/1, Georg Thieme Verlag,Stuttgart 1974, in H.-D. Jakubke and H. Jescheit, “Aminosauren, Peptide,Proteine”, Verlag Chemie, Weinheim, Deerfield Beach, and Basel 1982,and/or in Jochen Lehmann, “Chemie der Kohlenhydrate: Monosaccharide andDerivate”, Georg Thieme Verlag, Stuttgart 1974. The protecting groupsmay be removed at a convenient subsequent stage using methods known fromthe art.

The subject compounds can be synthesized via a variety of differentsynthetic routes using commercially available starting materials and/orstarting materials prepared by conventional synthetic methods. All ofthe compounds described herein (including prodrugs) can be prepared byadaptation of these methods.

Examples of synthetic routes that can be used to synthesize thecompounds disclosed herein are described in the Examples below.

Stereoisomers of the compounds can be isolated by procedures known tothose skilled in the art. The individual stereoisomers may be obtained,for instance, by a resolution technique or by chromatography techniques(e.g., silica gel chromatography, chiral chromatography, etc.).

Although the synthetic schemes discussed herein may not illustrate theuse of protecting groups, skilled artisans will recognize that in someinstances certain substituents may include functional groups requiringprotection. The exact identity of the protecting group used will dependupon, among other things, the identity of the functional group beingprotected and the reaction conditions used in the particular syntheticscheme, and will be apparent to those of skill in the art. Guidance forselecting protecting groups, their attachment and removal suitable for aparticular application can be found, for example, in Greene & Wuts,supra.

Prodrugs as described herein can be prepared by routine modification ofthe methods described herein. Alternatively, such prodrugs can beprepared by reacting a suitably protected compound with a suitableprogroup. Conditions for carrying out such reactions and fordeprotecting the product to yield prodrugs as described herein arewell-known.

In certain embodiments, in the above methods, the method furtherincludes separating isomers with a resolution technique. In certainembodiments, in the above methods, the method further includesseparating isomers with chiral chromatography. In certain embodiments,the disclosure provides a method for preparing an optically activecompound.

In some embodiments, the above methods further include the step offorming a salt of a compound disclosed herein. Embodiments are directedto the other processes described herein, and to the product prepared byany of the processes described herein.

EXAMPLES

The following examples are put forth so as to provide those of ordinaryskill in the art with a complete disclosure and description of how tomake and use the embodiments, and are not intended to limit the scope ofwhat the inventors regard as their invention nor are they intended torepresent that the experiments below are all or the only experimentsperformed. Efforts have been made to ensure accuracy with respect tonumbers used (e.g. amounts, temperature, etc.) but some experimentalerrors and deviations should be accounted for. As will be understood, bythose of skill in the art of organic synthesis and medicinal chemistrythe specific conditions set forth below are exemplary and can be variedor adapted to other reagents and products in routine fashion. Unlessindicated otherwise, parts are parts by weight, molecular weight isweight average molecular weight, temperature is in degrees Celsius, andpressure is at or near atmospheric. Standard abbreviations may be used.

Example 1 Preparation of Compounds Preparation of methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Oxalyl chloride (2.0 M in CH₂Cl₂; 15.2 mL, 30.3 mmol) was added dropwiseover 2-3 min to a stirred suspension of monomethylfumarate (2.63 g, 20.2mmol) in CH₂Cl₂ (80 mL) at 0° C. under nitrogen. After completeaddition, the mixture was stirred at 0° C. for 5 min then allowed towarm to room temperature and stirred for 3 hr (a yellow solutiondeveloped). A small aliquot was removed and quenched with MeOH. TLC ofthe reaction mixture indicated no acid was remaining. The mixture wasconcentrated under vacuum and CH₂Cl₂ (50 mL) was added to the residueand the mixture concentrated under vacuum once more to leave the acidchloride, which was used directly in the tetrazolone-forming step (yieldassumed quantitative=3.0 g). A safety notice for the procedure: Azidecompounds are potentially explosive. This reaction was performed behinda blast shield.

Azidotrimethylsilane (16.1 mL, 121.2 mmol) was added in one portion tothe acid chloride from the above procedure (3.0 g, 20.2 mmol) at roomtemperature (gas evolution was noted). The mixture was place undernitrogen and heated from room temperature to 100° C. (blocktemperature), then stirred at 100° C. for 90 min. After cooling to roomtemperature, the excess solvent was removed under vacuum to leave acrude residue. EtOAc (150 mL) and saturated NaHCO₃ (150 mL) were addedto the residue. A solid formed and the mixture was filtered. The filtercake was dissolved in H₂O (350 mL) and then combined with the saturatedNaHCO₃ layer of the filtrate. EtOAc (150 mL) was added to the combinedaqueous system and the mixture was acidified to about pH 3 with 1N HCl.The aqueous and organic layers were partitioned and the aqueous layerwas extracted with EtOAc (2×100 mL). The combined organic extracts weredried over Na₂SO₄, filtered and the solvent removed under vacuum toleave a crude residue (2.6 g; about 90% purity of desired product). Theresidue was purified by column chromatography on silica gel usingCH₂Cl₂/MeOH (1:0 to 9:1) as eluent to give the product (2.14 g, 62% over2 steps) as a solid. ¹H NMR (DMSO-d₆, 300 MHz): δ 7.73 (d, J=14.4 Hz,1H), 6.49 (d, J=14.4 Hz, 1H), 3.71 (s, 3H), −1.0 (br. s, 1H) ¹³C NMR(DMSO-d₆, 75 MHz): δ 165.7, 149.8, 132.3, 106.3, 51.9; m/z=169.34[M−H]+; HRMS (EI): [M+H]⁺ calc'd for C₅H₆N₄O₃ m/z 171.0518. found171.0522.

The above reaction can be scaled-up without loss of yield. Thetetrazolone-forming step with TMS-N₃ can also be conducted in solventssuch as 1,4-dioxane, without loss of yield. Additionally, afterpurification by column chromatography, the tetrazolone product can betriturated with MeOH and filtered, if required.

Preparation of methyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

K₂CO₃ (1.92 g, 14.0 mmol) was added in one portion to a stirred mixtureof methyl (E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (0.95 g,5.6 mmol) and iodomethane (0.7 mL, 11.2 mmol) in DMF (15 mL) at 0° C.under nitrogen. The mixture was stirred at 0° C. for 20 min, thenallowed to warm to room temperature and stirred overnight. LC/MSindicated complete reaction, so the mixture was poured in to H₂O (150mL) and EtOAc (50 mL). The aqueous and organic layers were partitionedand the aqueous layer was extracted with EtOAc (2×30 mL). The combinedorganic layers were dried (Na₂SO₄), filtered and the solvent removedunder vacuum to leave a crude residue, which was dry-loaded on to silicagel. The residue was purified by column chromatography on silica gelusing hexanes/EtOAc (1:0 to 1:1) as eluent to give the desired product(834 mg, 81%) as a solid. ¹H NMR (CDCl₃, 300 MHz) δ 7.88 (dd, J=14.4,0.6 Hz, 1H), 6.68 (d, J=14.4 Hz, 1H), 3.80 (s, 3H), 3.65 (s, 3H); ¹³CNMR (CDCl₃, 75 MHz) δ 166.2, 148.7, 132.2, 108.6, 52.2, 31.6; m/z=noparent-ion by LC/MS or HRMS. The above reaction can be scaled-up withoutloss of yield.

The following compounds can also be prepared using the above method.Each reaction utilized methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (170 mg, 1.0 mmol),alkylating agent (2 mmol) and K₂CO₃ (346 mg, 2.5 mmol) in DMF (3 mL) atroom temperature (no prior cooling to 0° C.).

Preparation of methyl(E)-3-(4-deuteriomethyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Product (159 mg, 85%) isolated as a solid after column chromatography[hexanes/EtOAc (1:0 to 3:2) as eluent]. ¹H NMR (CDCl₃, 300 MHz) δ 7.90(d, J=14.4 Hz, 1H), 6.70 (d, J=14.4 Hz, 1H), 3.82 (s, 3H); ¹³C NMR(CDCl₃, 75 MHz) δ 166.2, 148.7, 132.2, 108.6, 52.2 (note: ¹³C of CD₃ notobserved, or weak signal, under ¹³C NMR acquisition conditions);m/z=188.20 [M+H]⁺; HRMS (EI): [M+MeCN+H]⁺ calc'd for C₆H₅D₃N₄O₃+MeCN m/z229.1128. found 229.1138.

Preparation of methyl(E)-3-(4-deuterioisopropyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Reaction stirred at room temperature overnight, then heated to 50° C.and stirred for 2 hr. Product (60 mg, 27%) isolated as an oil aftercolumn chromatography [hexanes/EtOAc (1:0 to 3:2) as eluent]. ¹H NMR(CDCl₃, 300 MHz) δ 7.91 (d, J=14.4 Hz, 1H), 6.70 (d, J=14.4 Hz, 1H),3.82 (s, 3H); ¹³C NMR (CDCl₃, 75 MHz) δ 166.2, 147.9, 132.3, 108.3, 52.1(note: ¹³C of CD₃ (×2), or CD not observed, or weak signals, under ¹³CNMR acquisition conditions); m/z=220.21 [M+H]⁺; HRMS (EI): [M+H+MeCN]⁺calc'd for C₈H₅D₇N₄O₃+MeCN m/z 261.1693. found 261.1703.

Preparation of methyl(E)-3-(4-(2-(dimethylamino)ethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Reaction stirred at room temperature overnight, then heated to 50° C.and stirred for 2 hr. Product (60 mg, 25%) isolated as a solid aftercolumn chromatography [DCM/2N NH₃ in MeOH (1:0 to 95:5) as eluent]. ¹HNMR (CDCl₃, 300 MHz) δ 7.90 (d, J=14.4 Hz, 1H), 6.69 (d, J=14.4 Hz, 1H),4.07 (t, J=6.3 Hz, 2H), 3.81 (s, 3H), 2.74 (t, J=6.3 Hz, 2H), 2.28 (s,6H); ¹³C NMR (CDCl₃, 75 MHz) δ 166.3, 148.6, 132.3, 108.5, 56.9, 52.2,45.4, 43.2; m/z=242.17 [M+H]⁺; HRMS (EI): [M+H]⁺ calc'd for C₉H₁₅N₅O₃m/z 242.1253. found 242.1250.

General Procedure for the Alkylation of methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate with Alkyliodides orAlkylbromides Leading to methyl(E)-3-(4-alkyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

A stirring mixture of methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (1 eq), correspondingalkyliodide or alkylbromide (1.3 eq), Cs₂CO₃ (1.1 eq) and dry DMF (1mL/1 mmol) in a screw capped vial was heated at 45° C. for 4 h.Subsequently, reaction mixture was cooled to room temperature, dilutedwith EtOAc/H₂O and organic layer was separated. Upon extracting aqueouslayer with EtOAc, the combined organic layers were washed with water (5mL) and brine (3 mL) successively, stirred over anhydrous MgSO₄,filtered and concentrated by rotary evaporator under vacuum. Silica gelcolumn chromatographic (Combiflash Teledyne® with RediSep® silica gelcolumn) purification of thus obtained crude concentrate provided methyl(E)-3-(4-alkyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylates. Thefollowing analogs can also be prepared in the similar manner asdescribed herein.

Compound 6: Methyl(E)-3-(4-isopropyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 7.87 (d, J=14.4 Hz, 1H), 6.65 (d, J=14.4 Hz,1H), 4.50 (hept, J=6.8 Hz, 1H), 3.79 (s, 3H), 1.50 (d, J=6.8 Hz, 7H).¹³C NMR (75 MHz, CDCl₃) δ 166.31, 148.01, 132.35, 108.47, 52.21, 49.03,21.20. LC/MS: rt 4.62 min (B), purity 98%, MS (m/e) 213 (MH⁺).

Compound 13: Methyl(E)-3-(4-(2-methoxyethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 7.87 (d, J=14.4 Hz, 1H), 6.66 (d, J=14.4 Hz,1H), 4.16 (t, J=5.4 Hz, 2H), 3.80 (s, 3H), 3.75 (t, J=5.4 Hz, 2H), 3.35(s, 3H). ¹³C NMR (75 MHz, CDCl₃) δ 166.04, 148.43, 132.11, 108.44,68.70, 58.82, 52.02, 44.84. LC/MS: rt 5.51 min (A), purity 98%, MS (m/e)229 (MH⁺).

Compound 14: Methyl(E)-3-(4-(2-methoxy-2-oxoethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 7.89 (d, J=14.4 Hz, 1H), 6.69 (d, J=14.4 Hz,1H), 4.77 (s, 2H), 3.83 (s, 3H), 3.82 (s, 3H). ¹³C NMR (75 MHz, CDCl₃) δ165.88, 165.83, 148.12, 131.97, 108.85, 53.21, 52.07, 45.44. LC/MS: rt5.71 min (A), purity 98%, MS (m/e) 243 (MH⁺).

Compound 11: Synthesis of Methyl(E)-3-(4-cyclopentyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

To a solution of methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (1, 50 mg, 0.3 mmol)and cyclopentyl iodide (2, 68 μL, 115 mg, 0.6 mmol) in DMF (1 mL), DIEA(70 μL, 52 mg, 0.4 mmol)) was added. The reaction mixture was allowed tostir at 75° C. for 1.5 h, cooled down to room temperature and dilutedwith brine (20 mL). The resulting aqueous layer was then extracted withDCM (3×15 mL), and the combined organic layer was dried (MgSO₄),filtered and concentrated to give 125 mg of a brown residue. Columnchromatography (Combiflash Isco; 12 g Redisep column; eluted withhexanes for 5 min, 50% EtOAc/hexanes over 10 min till the desiredcompound eluted) provided 29 mg (41%) of a clear oil. ¹H NMR (300 MHz,CDCl₃) δ 7.87 (d, J=14.4 Hz, 1H), 6.66 (d, J=14.4 Hz, 1H), 4.63 (ddd,J=14.2, 7.8, 6.1 Hz, 1H), 3.80 (s, 3H), 2.20-1.83 (m, 6H), 1.82-1.67 (m,2H). ¹³C NMR (75 MHz, CDCl₃) δ 166.47, 148.41, 132.52, 108.60, 57.45,52.34, 31.87, 24.52. MS m/e: 239 (M+H)⁺.

Compound 12: Synthesis of Methyl(E)-3-(5-oxo-4-(tetrahydro-2H-pyran-4-yl)-4,5-dihydro-1H-tetrazol-1-yl)acrylate

A mixture of methyl (E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate(50 mg, 0.3 mmol), 4-iodotetrahydropyran (0.5 g, 2.4 mmol), DIEA (0.5mL, 371 mg, 2.9 mmol) and DMAP (50 mg, 0.4 mmol) was allowed to stir at75° C. overnight. The reaction mixture was cooled down to roomtemperature, diluted with brine (20 mL) and extracted with DCM (3×20mL). The combined organic layer was then dried (MgSO₄), filtered andconcentrated to give 560 mg of a brown residue. Column chromatography(Combiflash Isco; 24 g Redisep column; eluted with hexanes for 5 min,50% EtOAc/hexanes over 15 min till compound eluted) provided 17 mg (23%)of compound 12 as a white solid. ¹H NMR (300 MHz, CDCl₃) δ 7.89 (d,J=14.4 Hz, 1H), 6.68 (d, J=14.4 Hz, 1H), 4.37 (tt, J=11.5, 4.3 Hz, 1H),4.19-4.07 (m, 2H), 3.82 (s, 3H), 3.54 (td, J=11.9, 2.2 Hz, 2H),2.27-2.13 (m, 2H), 2.04-1.94 (m, 2H). ¹³C NMR (75 MHz, CDCl₃) δ 166.41,132.38, 108.97, 105.36, 66.90, 52.99, 52.43, 31.41. MS m/e: 255 (M+H)⁺.

Compound 19: Synthesis of Methyl(E)-3-(4-(2-hydroxy-2-methylpropyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

To a solution of methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (100 mg, 0.6 mmol)and 2,2-dimethyloxirane (1.1 mL, 890 mg, 12.4 mmol) in DMF (1 mL),cesium carbonate (230 mg, 0.7 mmol)) was added. The reaction mixture wasallowed to stir at 85° C. for 9 h, cooled down to room temperature anddiluted with water (25 mL). The resulting aqueous layer was thenextracted with DCM (3×20 mL), and the combined organic layer was dried(MgSO₄), filtered and concentrated to give 800 mg of a yellow residue.Column chromatography (Combiflash Isco; 12 g Redisep column; eluted withhexanes for 5 min, 50% EtOAc/hexanes over 10 min till the desiredcompound eluted) provided 42 mg (29%) of a white solid with 92% purity.Purification by HPLC provided 27 mg of compound 19 as a white solid. ¹HNMR (300 MHz, CDCl₃) δ 7.97 (d, J=14.1 Hz, 1H), 5.09 (d, J=14.1 Hz, 1H),3.73 (s, 3H), 3.46 (s, 2H), 1.53 (s, 6H). ¹³C NMR (75 MHz, CDCl₃) δ167.28, 153.87, 138.86, 99.79, 79.75, 54.45, 51.67, 27.75. MS m/e: 243(M+H)⁺.

Compound 7: Preparation of Methyl(E)-3-(4-((3-methyloxetan-3-yl)methyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

A mixture of methyl (E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate(0.10 g, 0.6 mmol), 3-(bromomethyl)-3-methyloxetane (0.15 g, 0.9 mmol),and K₂CO₃ (0.16 g, 1.2 mmol) in dimethylformamide (2 mL) was stirred at50° C. for 18 h After cooling to room temperature, the reaction mixturewas then partitioned between water and ethyl acetate. The organic layerwas separated, dried over sodium sulfate, filtered, and concentratedunder reduced pressure to give a residue, which was purified bychromatography eluting with ethyl acetate/hexanes (1/1) to providemethyl(E)-3-(4-((3-methyloxetan-3-yl)methyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylateas a pale white solid (0.12 g, 78%).

¹H NMR (CDCl₃, 300 MHz) 7.85 (d, J=14.5 Hz, 1H), 6.65 (d, J=14.5 Hz,1H), 4.64 (d, J=6.4 Hz, 2H), 4.42 (d, J=6.4 Hz, 2H), 4.17 (s, 2H), 3.78(s, 3H), 1.33 (s, 3H) ppm; ¹³C NMR (CDCl₃, 300 MHz) 166.87, 149.63,132.78, 109.36, 80.36, 52.36, 51.54, 40.55, 21.63 ppm; MS m/e: 255(M+H)⁺.

Compound 9: Preparation of Methyl(E)-3-(4-(methoxymethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

A mixture of methyl (E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate(0.10 g, 0.6 mmol), bromo(methoxy)methane (0.09 g, 0.7 mmol), and TEA(0.07 g, 0.7 mmol) in acetonitrile (2 mL) was stirred at roomtemperature for 18 h. The reaction mixture was then partitioned betweenwater and ethyl acetate. The organic layer was separated, dried oversodium sulfate, filtered, and concentrated under reduced pressure togive a residue, which was purified by chromatography eluting with ethylacetate/hexanes (4/6) to provide methyl(E)-3-(4-(methoxymethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate asa pale white solid (0.08 g, 63%)

¹H NMR (CDCl₃, 300 MHz) 7.86 (d, J=14.4 Hz, 1H), 6.66 (d, J=14.4 Hz,1H), 5.29 (s, 2H), 3.79 (s, 3H), 3.45 (s, 3H) ppm; ¹³C NMR (CDCl₃, 300MHz) 166.87, 149.14, 132.67, 109.39, 75.77, 58.22, 52.37 ppm; MS m/e:215 (M+H)⁺.

Compound 10: Preparation of Methyl(E)-3-(4-(dimethylcarbamoyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

A mixture of methyl (E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate(0.17 g, 1 mmol), dimethylcarbamic chloride (0.2 g, 1.9 mmol), and DMAP(0.17 g, 1.4 mmol) in toluene (5 mL) was stirred at 80° C. for 3 h Aftercooling to room temperature, the reaction mixture was then partitionedbetween water and ethyl acetate. The organic layer was separated, driedover sodium sulfate, filtered, and concentrated under reduced pressureto give a residue, which was purified by chromatography eluting withethyl acetate/hexanes (4/1) to provide methyl(E)-3-(4-(dimethylcarbamoyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylateas a pale white solid (0.14 g, 59%).

¹H NMR (CDCl₃, 300 MHz) 7.86 (d, J=13.8 Hz, 1H), 6.69 (d, J=13.8 Hz,1H), 3.83 (s, 3H), 3.15 (m, 6H) ppm; ¹³C NMR (CDCl₃, 300 MHz) 166.66,147.58, 146.57, 132.20, 109.90, 52.44, 38.70, 37.68 ppm; MS m/e: 242(M+H)⁺.

The following analogs were prepared in the similar manner as describedherein.

Compound 8: Methyl(E)-3-(4-(2-amino-2-oxoethyl)-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Compound 8 was prepared according to the method used to prepare Compound7.

¹H NMR (DMSO-d₆, 300 MHz) 7.77 (m, 2H), 7.45 (bs, 1H), 5.53 (m, 1H),4.64 (s, 2H), 3.73 (s, 3H) ppm; ¹³C NMR (DMSO-d₆, 300 MHz) 169.19,167.22, 149.66, 133.14, 108.11, 51.42, 46.27 ppm; MS m/e: 228 (M+H)⁺.

Method B:

Alternate synthetic method for the preparation of Alkyl (E orZ)-3-(4-alkyl/aryl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylates from1-alkyl/aryl-1,4-dihydro-5H-tetrazol-5 one

Alkyl (methyl or t-butyl) propiolate (1.3 eq) in dry acetonitrile (1mL/mmol) was added dropwise to a stirring solution of1-alkyl/aryl-1,4-dihydro-5H-tetrazol-5-one (1 eq) and DABCO (0.2 eq) indry acetonitrile (0.5 mL/mmol) at room temperature over a period of 20min. Upon complete addition of alkyl propiolate, clear homogeneousreaction was stirred at room temperature which transformed to darkreaction solution after 3 h (12 h for t-butylpropiolate). LC/MS andsilica gel TLC analysis of reaction aliquot indicated near quantitativeconsumption of 1-alkyl/aryl-1,4-dihydro-5H-tetrazol-5-one. Subsequently,reaction solution was concentrated to dryness and purified by CombiflashTeledyne® with RediSep® silica gel column. Three spots that wereobserved on the TLC were isolated independently and characterized by ¹HNMR as E regio-isomer [major product, alkyl(E)-3-(4-alkyl/aryl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylates], alongwith minor products corresponding to Z regio-isomer [alkyl(Z)-3-(4-alkyl/aryl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylates] anddialkyl (E)-hex-2-en-4-ynedioate (resulting from the homo coupling ofalkylpropiolate),

Compound 20: Dimethyl3,3′-(5-oxo-1H-tetrazole-1,4(5H)-diyl)(2E,2′E)-diacrylate

¹H NMR (300 MHz, CDCl₃) δ 7.88 (d, J=14.4 Hz, 2H), 6.72 (d, J=14.5 Hz,2H), 3.83 (s, 6H). ¹³C NMR (75 MHz, CDCl₃) δ 165.84, 145.87, 131.59,109.92, 52.45. LC/MS: rt 6.71 min (A), purity 98%, MS (m/e) 225(MH⁺—C₂H₅).

Compound 5: Methyl(E)-3-(4-ethyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 7.87 (d, J=14.4 Hz, 1H), 6.66 (d, J=14.4 Hz,1H), 4.03 (q, J=7.3 Hz, 2H), 3.80 (s, 3H), 1.46 (t, J=7.3 Hz, 3H). ¹³CNMR (75 MHz, CDCl₃) δ 166.06, 148.15, 132.11, 108.37, 52.01, 40.46,13.61. LC/MS: rt 5.96 min (A), purity 98%, MS (m/e) 199 (MH⁺).

Compound 22: Methyl(Z)-3-(4-ethyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 6.84 (d, J=9.8 Hz, 1H), 5.85 (d, J=9.8 Hz,1H), 4.02 (q, J=7.3 Hz, 2H), 3.79 (s, 3H), 1.45 (t, J=7.3 Hz, 3H). ¹³CNMR (75 MHz, CDCl₃) δ 164.57, 152.57, 124.72, 112.25, 52.08, 40.42,13.64. LC/MS: rt 5.13 min (A), purity 98%, MS (m/e) 199 (MH⁺).

Compound 15: tert-Butyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 7.74 (d, J=14.4 Hz, 1H), 6.57 (d, J=14.4 Hz,1H), 3.64 (s, 3H), 1.50 (s, 9H). ¹³C NMR (75 MHz, CDCl₃) δ 164.70,148.56, 131.12, 110.90, 81.47, 31.43, 28.04. LC/MS: rt 7.41 min (A),purity 98%, MS (m/e) 212 (MH⁺—CH₃).

Compound 23: tert-Butyl(Z)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 6.72 (d, J=9.8 Hz, 1H), 5.79 (d, J=9.7 Hz,1H), 3.63 (s, 3H), 1.49 (s, 9H). ¹³C NMR (75 MHz, CDCl₃) δ 163.20,148.75, 123.18, 115.16, 82.32, 31.40, 27.96. LC/MS: rt 6.55 min (A),purity 98%, MS (m/e) 212 (MH⁺—CH₃).

Compound 16: Preparation of Methyl(E)-3-(5-oxo-4-phenyl-4,5-dihydro-1H-tetrazol-1-yl)acrylate Step 1:Preparation of 1-phenyl-1,4-dihydro-5H-tetrazol-5-one

A safety notice for the procedure: Azide compounds are potentiallyexplosive. This reaction was performed behind a blast shield. A stirredmixture of azidotrimethylsilane (2.4 mL, 18 mmol) and benzoyl chloride(422 mg, 3.0 mmol) was heated from room temperature to 100° C. (blocktemperature) in a sealed vial with pressure-release cap. The mixture wasthen stirred at 100° C. overnight (Note: pressure develops duringheating). After cooling, the mixture was concentrated under vacuum andthe residue partitioned between EtOAc (10 mL) and a saturated aqueoussolution of NaHCO₃ (10 mL). The organic layer was extracted with afurther quantity of saturated aqueous NaHCO₃ (1×10 mL) [note: organiclayer assessed by TLC to ascertain if tetrazolone product completelyremoved. If tetrazolone still present in organic layer, then furtherextractions with saturated NaHCO₃ are used]. EtOAc (20 mL) was added tothe combined NaHCO₃ layers, and the pH was adjusted to <3 using 6N HClwith efficient stirring. The aqueous and organic layers were partitionedand the aqueous layer was extracted with EtOAc (2×10 mL). The combinedorganic layers were dried (Na₂SO₄), filtered and the solvent removedunder vacuum to afford the product (369 mg, 76%) as a solid. A samplewas recrystallized from EtOAc. ¹H NMR (DMSO-d₆, 300 MHz) δ 7.85-7.81 (m,2H), 7.57-7.50 (m, 2H), 7.41 (dt, J=7.5, 1.5 Hz, 1H), −1.3 (br. s, 1H);¹³C NMR (DMSO-d₆, 75 MHz) δ 150.3, 134.2, 129.5, 127.6, 119.5;m/z=163.18 [M+H]⁺ and 161.24 [M−H]⁺; HRMS (EI): [M−H]⁺ calc'd forC₇H₆N₄O m/z 161.0463. found 161.0532.

Step 2: Preparation of methyl(E)-3-(5-oxo-4-phenyl-4,5-dihydro-1H-tetrazol-1-yl)acrylate

¹H NMR (300 MHz, CDCl₃) δ 8.01-7.80 (m, 3H), 7.52 (t, J=7.7 Hz, 2H),7.41 (t, J=7.4 Hz, 1H), 6.74 (d, J=14.4 Hz, 1H), 3.83 (s, 3H). ¹³C NMR(75 MHz, CDCl₃) δ 165.93, 146.48, 133.85, 131.83, 129.65, 128.33,119.47, 108.88, 52.10. LC/MS: rt 7.68 min (A), purity 98%, MS (m/e) 247(MH⁺).

Compound 17: Preparation of Methyl(E)-3-(5-oxo-4-(pyridin-3-yl)-4,5-dihydro-1H-tetrazol-1-yl)acrylate Step1: Preparation of 1-(pyridin-3-yl)-1,4-dihydro-5H-tetrazol-5-one

A safety notice for the procedure: Azide compounds are potentiallyexplosive. This reaction was performed behind a blast shield. A stirredmixture of azidotrimethylsilane (2.4 mL, 18 mmol) and nicotinoylchloride (425 mg, 3.0 mmol) was heated from room temperature to 100° C.(block temperature) in a sealed vial with pressure-release cap. Themixture was then stirred at 100° C. overnight (Note: pressure developsduring heating). After cooling, the mixture was concentrated undervacuum and the residue partitioned between EtOAc (10 mL) and a saturatedaqueous solution of NaHCO₃ (10 mL). The organic layer was extracted witha further quantity of saturated aqueous NaHCO₃ (1×10 mL) [note: organiclayer assessed by TLC to ascertain if tetrazolone product completelyremoved. If tetrazolone still present in organic layer, then furtherextractions with saturated NaHCO₃ are used]. EtOAc (20 mL) was added tothe combined NaHCO₃ layers, and the pH was adjusted to <3 using 6N HClwith efficient stirring. Once acidified, the aqueous layer wasre-adjusted to pH 6-7 using saturated NaHCO₃. The aqueous and organiclayers were partitioned and the aqueous layer was extracted with EtOAc(2×10 mL). The combined organic layers were dried (Na₂SO₄), filtered andthe solvent removed under vacuum to afford the product (330 mg, 65%) asa solid. A sample was recrystallized from EtOAc. ¹H NMR (DMSO-d₆, 300MHz) δ 9.04 (d, J=2.1 Hz, 1H), 8.60 (d, J=4.5 Hz, 1H), 8.22 (ddd, J=8.4,2.7, 1.5 Hz, 1H), 7.58 (dd, J=8.4, 4.8, Hz, 1H), −1.1 (br. s, 1H); ¹³CNMR (DMSO-d₆, 75 MHz) δ 150.4, 148.5, 140.7, 131.1, 127.1, 124.2;m/z=162.20 [M−H]⁺; HRMS (EI): [M+H]⁺ calc'd for C₆H₅N₅O m/z 164.0572.found 164.0542.

Step 2: Preparation of methyl(E)-3-(5-oxo-4-(pyridin-3-yl)-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Method B to give the product as a solid. ¹H NMR (300 MHz, CDCl₃) δ 9.22(d, J=2.4 Hz, 1H), 8.67 (dd, J=4.8, 1.5 Hz, Hz, 1H) 8.30 (ddd, J=8.4,2.4, 1.5 Hz, 1H), 7.93 (d, J=14.4 Hz, 1H), 7.50 (dd, J=8.3, 4.8 Hz, 1H),6.75 (d, J=14.4 Hz, 1H), 3.82 (s, 3H). ¹³C NMR (75 MHz, CDCl₃) δ 165.69,148.76, 146.27, 140.17, 131.54, 130.93, 126.86, 124.14, 109.49, 52.18.LC/MS: rt 5.48 min (A), purity 98%, MS (m/e) 248 (MH⁺).

Compound 18: 2-(2,5-Dioxopyrrolidin-1-yl)ethyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

A homogeneous solution of tert-butyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (250 mg, 1.1mmol) and formic acid (2 mL) was stirred at room temperature. After 1 h,LC/MS analysis of the resulting white heterogeneous slurry indicatedcomplete consumption of tert-butyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate to(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylic acid. Uponconcentration of reaction mixture by rotary evaporator under vacuum, theresulting white solid was stirred in water (5 mL), suction filtered anddried to provide(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylic acid (110 mg,58%). ¹H NMR (300 MHz, DMSO-d₆) δ 12.78 (s, 1H), 7.67 (d, J=14.4 Hz,1H), 6.44 (d, J=14.4 Hz, 1H), 3.55 (s, 3H). ¹³C NMR (75 MHz, DMSO-d₆) δ166.82, 148.83, 132.58, 108.56, 31.72. LC/MS: rt 3.70 min (A), purity99%, MS (m/e) 212 (MH⁺+CH₃CN); rt 1.92 min (B), purity 99%, MS (m/e) 169(MH⁻). A single necked pear shaped round bottom flask containing a stirbar and (E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylic acid(100 mg, 0.58 mmol) was stoppered with a rubber septum and nitrogen wasintroduced. Dry CH₂Cl₂ (10 mL) was added and stirred for 5 min at 0° C.Subsequently, oxalyl chloride (0.3 mL, 430 mg, 3.4 mmol) was added tothe above reaction mixture all at once and stirred for 5 min. Catalyticamount of dry DMF [0.3 mL stock solution of dry DMF (0.1 mL) dissolvedin dry CH₂Cl₂ (4 mL)] was slowly added over a period of 3 min andstirred for 30 min. The resulting homogeneous solution was stirred atroom temperature for 2 h and concentrated by rotary evaporator undervacuum to dryness. DMAP (14 mg, 0.11 mmol),N-(2-hydroxyethyl)succinimide (100 mg, 0.69 mmol) and dry CH₂Cl₂ (7 mL)were transferred to above acid chloride and stirred at 0° C. After 10min, i-Pr₂NEt (0.3 mL, 220 mg, 1.76 mmol) was added drop-wise over aperiod of 5 min. After 30 min, the pale yellow homogeneous reactionmixture was stirred for 2 h at room temperature and concentrated byrotary evaporator under vacuum to dryness. The crude residue waspartitioned between EtOAc (20 mL) and water (8 mL). Organic layer wasseparated, stirred over anhydrous Na₂SO₄ and filtered. Uponconcentration of the filtrate, the crude residue was purified byCombiflash Teledyne® with RediSep® silica gel column 12 g using 30-70%EtOAc/hexanes as an eluting solvent to obtain2-(2,5-dioxopyrrolidin-1-yl)ethyl(E)-3-(4-methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate (95 mg, 55%)as a white solid. ¹H NMR (300 MHz, CDCl₃) δ 7.80 (d, J=14.4 Hz, 1H),6.57 (d, J=14.4 Hz, 1H), 4.34 ((t, J=5.2 Hz, 2H), 3.82 (t, J=5.2 Hz,2H), 3.63 (s, 3H), 2.70 (s, 4H). ¹³C NMR (75 MHz, CDCl₃) δ 176.95,165.32, 148.46, 132.52, 107.99, 61.44, 37.85, 31.46, 28.12. LC/MS: rt4.73 min (A), purity 98%, MS (m/e) 296 (MH⁺).

Compound 21: Preparation of methyl(E)-3-(4-cyclopropyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Step 1: Preparation of 1-cyclopropyl-1,4-dihydro-5H-tetrazol-5-one

A safety notice for the procedure: Azide compounds are potentiallyexplosive. This reaction was performed behind a blast shield.Azidotrimethylsilane (40 mL, 300 mmol) was added in one portion to astirred mixture of cyclopropanecarbonyl chloride (5.2 g, 50 mmol) at 0°C. under nitrogen. After complete addition, the cooling bath was removedand the mixture slowly heated to 100° C., then stirred at 100° C.overnight. After allowing to cool, the solvent was removed under vacuumto leave a crude residue. The residue was dry-loaded on to silica geland purified by column chromatography on silica gel using DCM/20% MeOHin DCM (1:0 to 1:1) as eluent to give the product as a solid. ¹H NMR(CDCl₃, 300 MHz) δ 3.33-3.25 (m, 1H), 1.20-1.12 (m, 4H); ¹³C NMR (CDCl₃,75 MHz) δ 154.0, 26.2, 5.9.

Step 2: Preparation of methyl(E)-3-(4-cyclopropyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate

Method B to give the product as a solid after purification by columnchromatography and high-performance liquid chromatography. ¹H NMR(CDCl₃, 300 MHz) δ 7.84 (d, J=14.4 Hz, 1H), 6.64 (d, J=14.4 Hz, 1H),3.81 (s, 3H), 3.26-3.32 (m, 1H), 1.14-1.21 (m, 4H); ¹³C NMR (CDCl₃, 75MHz) δ 166.2, 148.8, 132.2, 108.6, 52.2, 26.9, 6.1; m/z=211.13 [M+H]⁺&252.18 [M+MeCN+H]⁺; HRMS (EI): [M+MeCN+H]⁺ calc'd for C₈H₁₀N₄O₃+MeCN m/z252.1097. found 252.1105.

Example 2 Biological Activity of Compounds

Autoimmune Encephalitis (EAE) In Vivo Assay

Compounds disclosed herein were tested in an autoimmune encephalitis(EAE) in vivo assay in mice according to the methods described above inthe paragraph entitled B.2. Experimental Autoimmune EncephalomyelitisAnimal Model. Compound 1 (methyl(E)-3-(5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acrylate) significantlyprevented the onset of disease paralysis when dosed at 60 mg/kgbeginning on the day of immunization.

NrF2 Activation in a Whole Cell Nuclear Translocation Assay

Compounds were tested in a NrF2 (Nuclear factor (erythroid-derived2)-like 2) translocation assay by adapting the methods set forth in U.S.Pat. No. 8,101,373, the disclosure of which is incorporated herein byreference. The NrF2 activation exhibited by the present compoundsdemonstrates their anti-inflammatory activity.

Monomethyl fumarate and dimethyl fumarate exhibited NrF2 activation withEC50s of about 127 and 7.9 micromolar, respectively. As demonstrated inTable 3, compounds disclosed herein show comparable activity tomonomethyl fumarate and dimethyl fumarate in the NrF2 translocationassay. In addition to monomethyl fumarate and dimethyl fumarate,bardoxolone methyl was used as a positive control (data not shown).

TABLE 3

NrF2 translocation assay Compound X¹ R¹ EC₅₀ (μM) 1 —CH₃ H 61 2 —CH₃—CH₃ 9.9 6 —CH₃ —CH(CH₃)₂ 7.8 10 —CH₃ —C(O)N(CH₃)₂ 6.1 11 —CH₃-cyclopentyl 5.4 12 —CH₃ 4-tetrahydropyranyl 10.4 14 —CH₃ —CH₂C(O)OCH₃6.7 16 —CH₃ phenyl 1.0 17 —CH₃ 3-pyridyl 1.0 20 —CH₃

0.7 21 —CH₃ cyclopropyl 7.2

While the present invention has been described with reference to thespecific embodiments thereof, it should be understood by those skilledin the art that various changes may be made and equivalents may besubstituted without departing from the true spirit and scope of theinvention. In addition, many modifications may be made to adapt aparticular situation, material, composition of matter, process, processstep or steps, to the objective, spirit and scope of the presentinvention. All such modifications are intended to be within the scope ofthe claims appended hereto.

What is claimed is:
 1. A method of treating a disease or disorder in asubject in need thereof, the method comprising: administering to thesubject a pharmaceutically effective amount of a compound of formula(A):

wherein either: Y¹ is X^(a) and Y² is hydrogen, or Y² is X^(a) and Y¹ ishydrogen; wherein X^(a) is selected from carboxylic acid, carboxylester, heterocyclyl, substituted heterocyclyl, heteroaryl andsubstituted heteroaryl; and R¹ is selected from hydrogen, alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, substituted heteroaryland —R¹⁵, wherein R¹⁵ comprises a linking group and a compound offormula (A); or a salt or stereoisomer thereof, wherein theadministering is sufficient to treat the disease or disorder, andwherein the disease or disorder is psoriasis or multiple sclerosis. 2.The method of claim 1, wherein the compound is of formula (Ia) or (Ib):

wherein R¹⁵ comprises a linking group and a compound of formula (Ia) or(Ib).
 3. The method of claim 1, wherein X^(a) is a substitutedheterocyclyl or a substituted heteroaryl, wherein the substituent onX^(a) is X¹, wherein X¹ is C₁₋₆ alkyl or a progroup.
 4. The method ofclaim 1, wherein the compound is a compound of formula (IIa) or (IIb):

wherein R¹ is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl and —R¹⁵, whereinR¹⁵ comprises a linking group and a compound of formula (IIa) or (IIb);and X¹ is hydrogen, C₁₋₆ alkyl or a progroup; or a salt or stereoisomerthereof.
 5. The method of claim 4, wherein R¹ is aryl, substituted aryl,heteroaryl, or substituted heteroaryl.
 6. The method of claim 4, whereinR¹ is hydrogen, alkyl, substituted alkyl, cycloalkyl, substitutedcycloalkyl.
 7. The method of claim 6, wherein R¹ is hydrogen, methyl,ethyl, isopropyl, cyclopentyl, 4-tetrahydropyranyl, —CH₂CH₂OCH₃,—CH₂OCH₃, —CH₂C(O)OCH₃, or —CH₂CH(CH₃)₂OH.
 8. The method of claim 3,wherein X¹ is C₁₋₆ alkyl.
 9. The method of claim 7, wherein X¹ is methylor tert-butyl.
 10. The method of claim 3, wherein X¹ is a progroup ofthe formula:

wherein L¹ is a linking group; X² is optional and selected from O, N andS; R² is selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, acyl, aminoacyl,carboxyl, carboxyl ester, cycloalkyl, substituted cycloalkyl,heterocyclyl, substituted heterocyclyl, aryl, substituted aryl,heteroaryl, and substituted heteroaryl; and R³ and R⁴ are eachindependently optional and selected from hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, oxo,cycloalkyl, substituted cycloalkyl, heterocyclyl, substitutedheterocyclyl, aryl, substituted aryl, heteroaryl, and substitutedheteroaryl; or R² together with X² and either R³ or R⁴ form aheterocyclyl, substituted heterocyclyl, heteroaryl or substitutedheteroaryl.
 11. The method of claim 10, wherein X¹ is selected from:

wherein L¹ is a C₁₋₆ alkyl or substituted C₁₋₆ alkyl; R⁵ and R⁶ are eachindependently selected from hydrogen, alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, and substituted heteroaryl; or R⁵ and R⁶together with the nitrogen to which they are attached form aheterocyclyl, substituted heterocyclyl, heteroaryl or substitutedheteroaryl; and R⁷ is selected from hydrogen, alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, heterocyclyl, substituted heterocyclyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, and —OR¹⁴ whereR¹⁴ is selected from alkyl, substituted alkyl, alkenyl, substitutedalkenyl, alkynyl, substituted alkynyl, cycloalkyl, substitutedcycloalkyl, heterocyclyl, substituted heterocyclyl, aryl, substitutedaryl, heteroaryl, and substituted heteroaryl.
 12. The method of claim11, wherein X¹ is selected from:

wherein R⁸, R⁹, R¹⁰, R¹¹, R¹² and R¹³ are each independently selectedfrom hydrogen, alkyl and substituted alkyl.
 13. The method of claim 12,wherein R⁸ and R⁹ are each independently selected from hydrogen and C₁₋₆alkyl.
 14. The method of claim 13, wherein R⁸ and R⁹ are each hydrogen.15. The method of claim 13, wherein R⁸ is hydrogen and R⁹ is C₁₋₆ alkyl.16. The method of claim 12, wherein R¹⁰, R¹¹, R¹² and R¹³ are eachindependently selected from hydrogen and C₁₋₆ alkyl.
 17. The method ofclaim 16, wherein R¹⁰, R¹¹, R¹² and R¹³ are each hydrogen.
 18. Themethod of claim 16, wherein one of R¹⁰, R¹¹, R¹² and R¹³ is methyl andthe remaining are hydrogen.
 19. The method of claim 16, wherein two ofR¹⁰, R¹¹, R¹² and R¹³ are methyl and the remaining are hydrogen.
 20. Themethod of claim 1, wherein the linking group is—(CH₂)_(n)—Z_(y)—(CH₂)_(m)—, wherein n is an integer from 1 to 6; m is 0or an integer from 1 to 6; y is 0 or 1; and Z is O, NH, —O—P(O)(OH)—O—,S, S(O), SO₂ or —O—S(O)₂—O—.
 21. The method of claim 20, wherein thecompound has one of the following formulae:

wherein X^(1a) and X^(1b) are each independently selected from C₁₋₆alkyl and a progroup; and Z is O, NH, —O—P(O)(OH)—O—, S, S(O), SO₂ or—O—S(O)₂—O—.
 22. The method of claim 1, wherein R¹ is:

wherein X^(1b) is selected from C₁₋₆ alkyl and a progroup.
 23. Themethod of claim 22, wherein the compound has one of the followingformulae:

wherein X¹ and X^(1b) are each independently selected from C₁₋₆ alkyland a progroup.
 24. The method of claim 23, wherein X¹ and X^(1b) areeach independently a C₁₋₆ alkyl.
 25. The method of claim 24, wherein thecompound has the structure:


26. The method of claim 1, wherein the compound is selected from:


27. The method of claim 1, wherein the compound is selected from:

wherein X¹ is a progroup.